  The Network Administrator's Guide V0.4

  Olaf Kirch
  1999 8 15
    lvl@chollian.net, ŵkaien@aapd.metal.pusan.ac.kr

   8  Ǿ ֽϴ. ޺κ   ּ !
  ______________________________________________________________________

  

  1. Introduction to Networking
     1.1 
     1.2 UUCP Networks
        1.2.1 UUCP ϴ 
     1.3 TCP/IP Networks
        1.3.1 Introduction to TCP/IP-Networks
        1.3.2 Ethernets
        1.3.3 Other Types of Hardware
        1.3.4 The Internet Protocol
        1.3.5 IP over Serial Lines
        1.3.6 The Transmission Control Protocol
        1.3.7 The User Datagram Protocol
        1.3.8 More on Ports
        1.3.9 The Socket Library
     1.4 Linux Networking
        1.4.1 Different Streaks of Development
        1.4.2 Where to Get the Code
     1.5 Maintaining Your System
        1.5.1 System Security

  2. Issues of TCP/IP Networking
     2.1 Networking Interfaces
     2.2 IP Addresses
     2.3 Address Resolution
     2.4 IP Routing
        2.4.1 IP Networks
        2.4.2 Subnetworks
        2.4.3 Gateways
        2.4.4 The Routing Table
        2.4.5 Metric Values
     2.5 The Internet Control Message Protocol
     2.6 The Domain Name System
        2.6.1 Hostname Resolution
        2.6.2 Enter DNS
        2.6.3 Name Lookups with DNS
        2.6.4 Domain Name Servers
        2.6.5 The DNS Database
        2.6.6 Reverse Lookups

  3. Configuring the Networking Hardware
     3.1 Devices, Drivers, and all that
     3.2 Kernel Configuration
        3.2.1 Kernel Options in Linux 1.0 and Higher
        3.2.2 Kernel Options in Linux 1.1.14 and Higher
     3.3 A Tour of Linux Network Devices
     3.4 Ethernet Installation
        3.4.1 Ethernet Cabling
        3.4.2 Supported Boards
        3.4.3 Ethernet Autoprobing
     3.5 The PLIP Driver
     3.6 The SLIP and PPP Drivers

  4. Setting up the Serial Hardware
     4.1 Communication Software for Modem Links
     4.2 Introduction to Serial Devices
     4.3 Accessing Serial Devices
     4.4 Serial Hardware

  5. Configuring TCP/IP Networking
     5.1 Setting up the proc Filesystem
     5.2 Installing the Binaries
     5.3 Another Example
     5.4 Setting the Hostname
     5.5 Assigning IP Addresses
     5.6 Writing hosts and networks Files
     5.7 Interface Configuration for IP
        5.7.1 The Loopback Interface
        5.7.2 Ethernet Interfaces
        5.7.3 Routing through a Gateway
        5.7.4 Configuring a Gateway
        5.7.5 The PLIP Interface
        5.7.6 The SLIP and PPP Interface
        5.7.7 The Dummy Interface
     5.8 All About ifconfig
     5.9 Checking with netstat
        5.9.1 Displaying the Routing Table
        5.9.2 Displaying Interface Statistics
        5.9.3 Displaying Connections
     5.10 Checking the ARP Tables
     5.11 The Future

  6. Name Service and Resolver Configuration
     6.1 The Resolver Library
        6.1.1 The host.conf File
        6.1.2 Resolver Environment Variables
        6.1.3 Configuring Name Server Lookups -- resolv.conf
        6.1.4 Resolver Robustness
     6.2 Running named
        6.2.1 The named.boot File
        6.2.2 The DNS Database Files
        6.2.3 Writing the Master Files
        6.2.4 Verifying the Name Server Setup
        6.2.5 Other Useful Tools

  7. Serial Line IP
     7.1 General Requirements
     7.2 SLIP Operation
     7.3 Using dip
        7.3.1 A Sample Script
        7.3.2 A dip Reference
           7.3.2.1 The Modem Commands
           7.3.2.2 echo and term
           7.3.2.3 The get Command
           7.3.2.4 The print command
           7.3.2.5 Variable Name
           7.3.2.6 The if and goto command
           7.3.2.7 send, wait and sleep
           7.3.2.8 mode and default
     7.4 Running in Server Mode

  8. The Point-to-Point Protocol
     8.1 Untangling the P's
     8.2 PPP On
     8.3 Running pppd
     8.4 Using Options Files
     8.5 Dialing out with chat
     8.6 Debugging Your PPP Setup
     8.7 IP Configuration Options
        8.7.1 ChoosingIPAddresses
        8.7.2 Routing Through a PPP
     8.8 Link Control Options
     8.9 General Security Considerations
     8.10 Authentication with PPP
        8.10.1 CHAP versus PAP
        8.10.2 The CHAP Secrets File
        8.10.3 The PAP Secrets File
     8.11 Configuration a PPP Server

  ______________________________________________________________________

  1.  Introduction to Networking

  1.1.  

  Ʈŷ ϰ   Ƹ Ÿŭ Ǿ ̴. 
  ô , Ҵ   غ,   ǻ縦 ϱ
  ؼ,   Դ. 'A'      ,
  'B'  ڱ ʴϰ  ;Ѵٰ .  ׷,
  ׵ ʹ ָ   ֱ , 'A'  ļ 'B'
  鸮Բ  . ׷ 'A'   ־ ٸ  ? 1) ״
  'B' ִ ҷ  ɾ   ־,  Ŀٶ  
   ־, ׵ ̿ ߰뿡     'C' ޽
  ϰ   ־.    ٷ Ʈŷ̴.

  , Ʈŷ 츮      
  ̴. ,  ౸{{.   ̿ 
  ٺ Ư  ְ ִ.   ϱؼ, м
  ũο̺  Ŵ θ  ؼ μ ⸦ ְ
   ִ ǻ͸   ִ.   ġ 
  ؾ, ౸  ̾߱ Ӹ ƴ϶, ̷  ̷
  Ե   ؼ ٷ ̴.

  츮  ȳ    Ʈŷ , UUCP ʷ  Ͱ
  TCP/IP    ٷ  ̴. ̰͵  ǻ ̿
  ͸ ϱ⿡   ̸, Ʈ Ű̴. 
  忡,   ΰ Ʈŷ  ⺻  信 ؼ 
  ̴.

  츮 Ʈũ ڰ ͸  ִ  ȣƮ
  񽺿   ν  ǻͿ   ִ host 
  Ǹ . ȣƮ ǻ ϶  ְ, ׷   ִ;
    ȣƮ X-terminal̳ ڸƮ Ͱ   ִ. ұԸ
  host  site θ⵵ Ѵ.

          ڵ  ľ̴   Ұϴ.  ̷
     ѰϿ protocols ̶ θ.   ⿡
     ƾ Ѵ. ̸׸   尡   
  ڵ   ¸ ߾ 캸ƶ. ſ  
  ·ν, ǻͿ ϴ ݵ Ʈũ   ̻
  ȣƮ ̿ ޽  ȯϱ   Ģ  ʴ´.

  1.2.  UUCP Networks

  UUCP Unix-to-Unix Copy  ̴. α׷ Ű  
  ϴ      ؼ  ϰ, ۵ 
  ϸ, Ʈ Ʈ ִ    α׷ ۽Ų.
  70 Ĺݿ ù  ģ ķ  ȭ ޾ Ծ , װ
  ϴ 񽺵  ĸŸ  ִ. ̰ ֿ
   ̼  ̾ ȭ   ϰ ִ  
   Ÿ  Ѵ.

  ó UUCP 1977  ҿ н  Ʈ   ϱ
    Ǿ. 1978߹ݿ,  Ʈũ  80 Ʈ
  Ǿ. ̰ Ʈ  Ӹƴ϶ ø̼ν
  ڿ ǰ ־. ׷  ýۿ   ϴ 
  ο Ʈ ϰ, ׸ ġ ̾.  ô뿡
    ȭŰ ߴ.  ó UUCP  ̻ UNX ѵǾ
   ʴ.  ׸  AmigaOS, DOS, Atari's TOS  پ ÷
    ִ   Ʈ ִ.

  UUCP Ʈũ ֿ ߿ ϳ 뿪 ٴ ̴.  ,
  ִ ۷  ȭ     ٴ ̴.
  ٸ δ UUCP ũ    ̴; ſ
  ȣƮ   Ģ  ΰ   ̾  Ѵ.
  ׷Ƿ, κ ð  ޽ UUCP Ʈũ ۽Ű 
   Һȴ. ׷  ȣƮ ũ ϴ  հŸ
  Ǹ,      ð ٸ ȴ.

  ̷ ѿ ұϰ,   UUCP Ʈũ 迡
  ǰ ,  ڵ    Ʈũ
  ϰ  ִ. UUCP α ִ   ֿ δ The Big
  Internet Cable Ǿ ִ   ǻͿ    
  ſ δٴ ̴. UUCP 带  ǻͷ   UUCP 
    ϳ  ʿϸ,  ٸ UUCP 尡 ϰ  
  ޴  Ⲩ    ̴.

  1.2.1.  UUCP ϴ 

  UUCP װ ̸ ñⰡ  ܼϴ: װ ⺻ ϳ
  ȣƮ   ȣƮ  Ѵ. װ  Ʈ
  ȣƮ󿡼 Ȯϰ ۾ Ų .   ǻͰ
  swim̶  ̸     ȣƮ  ؼ, μ   
  lpr Ѵٰ . ׷   swim  - bash  (GNU
  Bourne  Again Shell)  ,  ǥ(!) 
    𸥴. ֳϸ bash װ history ڷ ϱ
  ̴.  󿡼  å μϱ  ࿡  Է 
  ִ.

       $ uux -r swim!lpr !netguide.dvi

  UUCP  ɾν uux swim   ϳ job  Ѵ.
   ۾    netguide.dvi ̷ ,   lpr
  ֱ⸦ û  ̴. -r ɼ uux  Ʈ ý
  θ ʰԲ ش.    Ȯ    ۾
  ش. ̷ ۾ spooling̶ θ.

  UUCP  ٸ Ưδ,  ȣƮ  ļ ۾ ϵ
  ǥȭ ش  ̴.    swim̶   ȣƮ
  groucho  ϳ UUCP  ٰ . groucho UNIX
  ø̼ Ŵ ī̺긦 ش.   Ʈ
  tripwire-1.0.tar.gz   ٿε ϱ      
   ִ.

       $ uucp -mr swim!groucho!~/security/tripwire-1.0.tar.gz trip.tgz

   ۾ grouchoκ     swim û
  ̸,     Ʈ ش. UUCP  
  trip.tgz  ̸,       п
  뺸  ̴. ̰  ܰ Ǿ ִ. ù ° ܰ  
  Ʈ swim  ۾ ش.    ܰ swim groucho 
    ,   ٿεѴ. , swim 
    ȣƮ    Ѵ.

  ó UUCP Ʈũ ϴ  ߿ 񽺷δ ڿ
   ִ.  츮 ߿ ̷ ͵ ٷ  ̴. ̰͵鿡
    Ұ踦  ܶ  ְ ִ.

  ڿ -  Ұ -   ̷ ȣƮ ϴ  
   Ʈ ȣƮ  ִ ڵ  ޽ ȯϱ 
  ڿ  ̴.   Ʈ  Ʈ ޽
   ۾  ó ýۿ   ȴ. UUCP ȯ濡,
     ּҿ  ޽ Ϸ  ϴ ȣƮ 󿡼
  밳 rmail  ָ   ϰ ȴ. rmail  ޽
  ٸ ȣƮ  ϰ Ǹ,  ޽   ȣƮ ϰ
  ȴ. 츮  κ  13忡 ڼϰ ٷ ̴.
  News Խ ýۿ   зǾ Ǿ ִ. 밳
  ̷ ¸    θ, ̰ ϰ ִ Ʈ
    120,000 ϴ   ȯ   θ ˷ ִ.
    ʹ 1979 Ž ö , ο Unix V7
  Բ UUCP  Ŀ,   Unix ȯϿ Ϲ 
   ȯڴ  Ͽ. ׵   ũƮ 
  α׷ ۼϿ, ̰     ݴ   ý  Ǿ.
  1980⿡    Ʈũ North Carolina п  
   Ʈ duke, unc ׸ phs  Ͽ.  ׸ ,
   ħ ϱ Ͽ.   UUCP 
  ϴ  Ʈũӿ ұϰ,  ̻ ϳ  
  Ʈũ  ʴ .

   ־  ⺻  ̴. ϳ  ȭ
  ׷ Ư   Ǵ  Խ ̴. 
  ׷ κ Ʈ ϰ Ǹ, ġִ  Ϸ翡
  60MB ϵȴ.

  UUCP  迡,    û   ׷κ     
  Ƴ,      batches  ϴ  װ͵ , UUCP
  ũ ļ  ȴ. ̰͵   Ʈ  Ǹ,
  ߿ ̰͵ Ǯ ؼ rnews  ϸ ȴ.

  , UUCP   ϱ    ̾ 
  ī̺ Ʈ  øü   ִ.  UUCP 
  װ͵ ̾ ϰų, guest ڷ αؼ,  Ʈ 
   ,  ٰ ī̺    ϵ
  ۹     ִ.  ̵  guest   밳  α
  н uucp/nuucp Ǵ ׿  ͵ .

  1.3.  TCP/IP Networks

   UUCP ϴ   ε Ʈũ   
  ִٴ ̶ , store-and-forward  ٷ 
  °   Ǿ.    Local Area Networks (LANs).
  ̷ ͵ 밳   ̳    ġϰ ִ
  Ҽ ǻͷ Ǿ ִ. װ  ۾ȯ ֱ
   Ǿ ִ. ,   ̷ ȣƮ ̿
   ϰų, ٸ 迡 ִ ø̼ǵ ϰ
  ; ̴.

  ̷ ۾ Ʈũ   ,  ٸ ٹ ʿϴ.
  ۾ñ⿡   ü ߼ ʰ,  ڷḦ  
   (Ŷ)  ,  ȣƮ   ,   װ͵   ִ
       ߼Ѵ.      Ʈũ   ¸ packet-switched
  Ʈũ θ. ٸ Ʈũ ߿ ̰  Ʈũ 
  ȭ ø  ϱ  ̴.  Ʈ
  鿡    .

  UNIX ý۰  UNIX Ʈ  ִ ذν TCP/IP
  ˷  äϰ ִ.   TCP/IP  
   ٷ ȴ.

  1.3.1.  Introduction to TCP/IP-Networks

  TCP/IP 1969  漺 DARPA (Defense Advanced  Research
  Projects Agency)   Ʈ Ͽ.  ̰ ARPANET
   Ʈũν  1975⿡ Ϲε鵵 밡 · ȯǾ.

  1983⿡, ο   TCP/IP ǥ ݷ
  äõǾ,   Ʈ ũ ִ  ȣƮ  Ʈũ
  ϱ  TCP/IP  ʿ    Ǿ. ARPANET ħ
  ͳ (1990, ARPANET  ü  ٸ ·  Ѱ)
  Ͽ  TCP/IP   ͳ Ѱ踦 Ѿ  Ʈũ
   .  ָ  δ UNIX  Ÿ  
  , ISDN      ȭ    , װ
   ̷ ̾ Ʈũ  ۵ ϸ .

    TCP/IP   ڻ     Ѵ. ϳ
    ڸ, Fredland 򰡿 ġϰ  Groucho Marx
  University (GMU)   ̴.   μ ϳ 
  ϴ 쵵 ְ,    κ μ ü ϳ
    ,  ٸ  ϳ μ    
  찡  . ̰͵  Ǿ , ܵ  ũ Ͽ
  ͳ ⵵ Ѵ.

   ǻͰ Mathematics Department ִ UNIX ȣƮ (
  ̸ erdos)  LAN Ǿ ִٰ . quark  θ
  Physics Department ִ ȣ Ʈ ϱ ,   
  Է϶.

       $ rlogin quark.physics
       Welcome to the Physics Department at GMU
       (ttyq2) login:

  Ʈ, andres   ϴ    α н带
  Է϶.  ׷ quark  ġ ý ܼ ȯ濡  
  ִ ó,  Է  ְ ϱ  , ϳ  ش. 
    , ٽ  ڽ  ǵ   ȴ.
   ÿ ۿ  ִ ,  TCP/IP ϰ ִ ȭ
  ø ̼ remote login Ͽ Ծ.

   quark    ÷ α׷̳, PostScript
  previewer   ɰ , X11  ϴ ø̼  ;
   𸥴.  ȣƮ ȭ ̷ ø̼ ϱ
  ؼ DISPLAY ȯ  ؾ Ѵ:

       $ export DISPLAY=erdos.maths:0.0

   ø̼   Ųٸ, quark ſ X 
  ϰ   ̰, ȭ鿡 Ǯ  ǥ ̴. ,  ̰
   erdos󿡼 X11  ų ʿ䰡 ִ. ⿡ ִ   
  TCP/IP quark erdos 㰡ϴ ̸,   δ X11 Ŷ
  , ڷδ  ܵ ýۿ ִ Ͱ    . 
  Ʈũ  ⿡ յڰ ϰ Ǿ ִ.

  TCP/IP Ʈũ  ϳ ߿ ø̼δ NFS (ǥ
  Network Fiie Sy stem)   ִ. ̰ Ʈũ  ǥϴ
  Ǵٸ ̴. ֳϸ, װ  ⺻ ٸ ȣƮκ
  丮  Ʈϱ ̴. ׷,  װ͵  
  ý Ÿ.  ,  Ȩ ͸ LAN ִ
  ٸ  ȣƮ ͸ Ʈν, ߾   
  ִ.  ۾   ڵ  ȣƮ    ,
   Ȩ ͸ ִ   ߰ϰ ȴ. ϰ,  
   迡 TEX  Ŵ  ũ   
  ø̼ ġϴ ̳, ٸ 迡 ̷ ͸
  ϴ ͵  ϰ Ǿ. 츮 11忡 NFS  ڼϰ
  ٷ ̴.

  , ̰͵ TCP/IP Ʈũ    ִ  Ѱ
   Ұϴ.  TCP/IP Ʈũ  ɼ ٺ  ִ.

  츮  TCP/IP   ִ      ִ.
   ϵ  鼭, ۾  .

  1.3.2.  Ethernets

  LAN ؼ ϴ ϵ ߿ Ϲ  θ
  ϴ  Ether- net̴. ̴ Ŀ, ̳ Ʈ ù
  Ͽ װͿ ϰ Ǵ ϳ ܵ ̺ ̷ִ. ʴ
  10M bit   ִ ̴ ״  ʱ   
  α⸦ ϰ ִ.

  ̴ݿ   ⺻  , thick, thin ׸ twisted pair
  ̷ ִ.  Thin Thick ̴ݴ   ϳ ̺
  ϰ  . 뿪   ̺ ȣƮ ӽŰ
   ٸ. Thin Ethernet μ ӵǾ ִ T  "BNC"
  Ŀ͸ ǻ ޺κп  ִ ÷׿ Ⱦ ִ´. Thick  Ethernet
   ̿ؼ    հ, ű⿡ Ʈ ù Ⱦ ִ´.
   ȣƮ Ʈ  ù   ִ. Thin  thick
  Ethernet   ִ 200 Ǵ 500ͱ    ְ, ̰
  10base-2 ׸ 10base-5 θ. Twisted pair   ȭ ġ
  ã  ־,    ̷ ̴̺.  ׷ 밳
  10base-T  ˷ ϵ ߰ ʿϴ.

   thick Ethernet 彺Ʈ ߰Ű ۾ ణ 
  , װ  Ʈũ ߸ ʴ´. thinnet ġ
  ȣƮ ߰ϱ ؼ,  и  Ʈũ 񽺸
  ߴܽ ξ Ѵ. ֳϸ, ĿͿ   ߶  ϱ
  ̴.

  κ   δٴ  thin Ethernet  ϴ
   ִ: PC ī  US ޷ $50 ǰ,  ʹ
  2 3Ʈ̴. ׷   ʿ ϴ  thick
  Ethernet  ϴ.  ,  GMU кδ thick Ethernet
  Ѵ. ׷, Ʈũ ȣƮ ߰   񽺸
  ߴܽŰ    ̴.

  ̴  ̶ Ѵٸ, ̺ ̿  ִٴ ̴.
  ׷, LAN  , ذ Ǵ κ̴. ׷,  ̴
  κе , 긴, Ǵ  ͸ ؼ, θ  
  𸥴. ʹ ܼ   ̻ ҵ ̿ ִ ȣ
  Ѵ. ׷,  κе ϳ ̴ ó ൿѴ. ʿ
   ̶, Ʈũٰ   ȣƮ  ̻ ȣƮ
  ޼.  긮 ʹ  ϰ Ǿ ִ. ̰͵
   ͸ мؼ,  ȣƮ  ȣƮ ٸ,
  װ   .

  ̴ ϳ ȣƮ  ̴ݻ  ִ ٸ ȣƮ ְ
  1500Ʈ  Ŷ (Ǵ ) ִ  ýó ۵Ѵ. 
  ȣƮ ̴  ߿  Ʈ ּȭǾ ִ. ̷
  ּҵ 밳    ڰ ݷ Ǿ   
  ִ.  , aa:bb:cc:dd:ee:ff.

   ϳ ̼ ġ ӵǾ ִ  ̼ó
  ̰Բ ؼ  .   ȣƮ  ̼
  ãƳ óѴ.     ̼  ÿ 
  õ , ߻ϴ 浹    ̼ ⸦ Ŵ
  ν ׷  ذǸ, Ŀ õѴ.

  1.3.3.  Other Types of Hardware

  Groucho Marx University  Ŵ ҿ, ̴ݴ  ϳ
  · Ǵ  ƴϴ. Groucho Marx University, LAN 
  δ campus backbone   ְ, װ FDDI (Fiber
  Distributed Data Interface) ϴ м ̴.  FDDI
   ڷḦ  ٸ Ͽ Ѵ. ̰ ⺻,
  ⿡   ٽøؼ,   װ ū Ѵٸ ϳ
  ̼      㰡ϰ  tokens 
  Ѵ.  FDDI ֿ    δ 100Mbps  ӵ   ְ,
  ִ ̰ ְ 200km ϴٴ ̴.

  հŸ Ʈũ ϱ , ٸ  谡  Ǹ,
    X.25  ʸ ΰ ִ. U.S. ִ Tymnet Ͽ ִ
  Datex-P  Public Data N- etwork  񽺸  ϰ ִ.
  X.25 ,  Packet Assembler/Disassembler  Ǵ PAD  Ư
  ϵ ʿ Ѵ. X.25 Ʈŷ  Կ ұ
  ϰ, TCP/IP ׸ ٸ  ϰ ִ Ʈũ ϱ
     ȴ. IP Ŷ X.25 ϰ ǥ  Ե
  Ŀ, װ͵ ܼ X.25 ο Ʈũ  ȴ.

  ,  Ƹ߾ Ʈũ ϱ  밳  ׵ ǻ͸
    Ѵ: ̰ packet radio Ǵ ham radio θ. ham
  radio      츮 AX.25 θ. ̰
  X.25  ̴.

  ٸ δ ü     ̾  
  ø  ϰ ִ. ̰͵  Ŷ  ,
  SLIP PPP   ٸ   ʿ Ѵ. ̰ Ʒ
  Ǿ ִ.

  1.3.4.  The Internet Protocol

    Ʈũ ϳ ̴ ϱ ġ  ̴.
  ̻  ,  ϵ ϰ ִ Ǵ 󸶳 
  Ʈ  ִ   Ʈũ ϰ ;
  ̴.   , Groucho Marx University   Ŵ ҿ,
   밳    ؾ ϰ,  иǾ  
   ̴ݸ   ̴. GMU, кδ   ̴s
  Ѵ: ϳ ̳    踦 ϴ
  Ʈũ  ٸ ϳ л      踦 ϴ
  Ʈũ ִ. Ѵ FDDI campus backbone   ִ.

    ̸ gateway ϴ   ȣƮ  óȴ.
  Ʈ̴   ̴ݰ м ̿ װ͵
  ν,   Ŷ   Ŷ óѴ.  ,
    Maths  Department ְ,   ǻͿ Physics
  Department LAN  ִ quark ȣƮ ϰ ʹٸ, Ʈŷ 
  Ʈ  Ŷ quark     . ֳϸ, 
  ̴ݻ  ִ   ϱ ̴. ׷ Ʈ̰ ۾
   Ѵ.  麻 ؼ, sophus    Ʈ̴
  Physics Department ִ   Ʈ niels ̵ Ŷ 
  . niels  ȣƮ Ŷ ϴ  Ѵ. erdos
  quark  帧 ׸ 1.1  ִ.

               ׸ 1.1: erdos quark ڷḦ  ܰ  

  Ʈ ȣƮ  ڷ   ȹϴ  ۾ routing
  ϸ,  ̷   , Ŷ 밳 datagrams ȴ. ̷
  ۾ ϰ  ϱ , ϵ   Ǵ ܵ
   , IP Ǵ Internet Protocol ڷ ȯ۾  Ѵ.
  2忡, IP ÿ    ϰ ٷ ̴.

  IP ֿ δ  ٸ Ʈũ ܰ 
  Ʈũ  ȭ ش.  ̰   ͳƮŷ̶  ϰ,   
     ߻ϴ  "meta-network" internet  θ. ⿡ an
  internet the Internet ̹  ִٴ  ϶.

  , IP  ϵ   巹ϴ ۾ ʿϴ.
  ̷  ۾ IP 巹 θ ϳ Ϲ 32Ʈ  
  ȣƮ Ҵν  ϼ . ϳ IP 巹 밳  
   Ʈڷ س, ڸ 8Ʈ й ´. 
  , quark 0x954C0C04 IP 巹  ְ, װ ٽ
  149.76.12.4 ǥѴ. ̷ ¸ dotted quad notation̶
  θ.

   ׷,  츮   ٸ  ּҸ  ִٰ
   ̴. , ù ° quark   ȣƮ, ׸ IP 巹,
  , 6Ʈ ̴ ּҿ  ϵ ּҰ ִ.
  ¶簣, ̷   ּҵ ϳ ġؾߵȴ.  ,
   rlogin quark  Էϸ, Ʈŷ Ʈ quark  IP
  巹   ְ ȴ. , IP  ڷḦ Physics Department's
  ̴ݷ  Ѱ , װ ؼ  ̴ 巹 IP
  巹 ġѾ Ѵ.

    ؼ ڼϰ   , 2忡 ̰ ٷ
  ϰڴ.    hostname resolution̶ θ ּҵ ã
  ܰ ȣƮ  IP 巹  ġŰ , ڵ ϵ
  ּҷ ġŰ   ϴ ͸ε  .

  1.3.5.  IP over Serial Lines

   ø ο, SLIP Ǵ Serial Line IP ˷ ǥ
    δ.  CSLIP Ǵ compress SLIP SLIP Ų
  ̸, ̰ ø ũ    뿪  
  ϱ ؼ IP  ϴ ۾ Ѵ.  - SLIP RFC 1055
  Ǿ ִ.  ϴ  ۾ ϴ CSLIP RFC 1144 
  ؼ, Ǿ ִ.  PPP Ǵ Point-to-Point Protocol̶   ϴ 
  ٸ   ø  ִ.  PPP SLIP   Ư¡ 
  ִ. SLIP  ϴ PPP ֿ  δ IP
  ͱ׷ ϴ   ٴ  ̴. װ ޵Ǵ
     ͱ׷   ְԲ ۵Ǿ ִ.

  1.3.6.  The Transmission Control Protocol

    ϳ ȣƮ ٸ ȣƮ  ڷḦ  ɸ
  ִ   ƴ .   quark ϰ Ѵٸ, erdos
  ִ rlogin μ quark  ִ  μ ̿   ִ
    ; ̴. ׸Ͽ,     ̰
  ۽ű⿡  Ŷ  Ǹ,  ű⿡   Ʈ
  ٽ  Ǵ ̴.  ̰  ó  ſ 
  ۾  ϰ ִ.

  IP   ſ ߿ϱ  ׷   ִ  ƴϴ.
   E- thernet ִ    GMU FTPκ
  XFree86 ֽ  ۹޴ ٰ . ⼭ ߻ϴ Ϸ
  Ƿ û ̸, ̰ Ʈ̰ ó ̴. ֳϸ,
  ۼӵ ſ  ̰, ޸    𸣱 
  .    quark Ŷ   Ѵٸ, sophus
  õ    𸣱  ׷  ϱ
  ƴ. IP ܼϰ װ  ν ׷  ذѴ.
  ׷ Ŷ , װ  ٽ Ǻθ  .  ͸
  ϰ ϼϸ,  ãƳ ϴ   ȣƮ
  ֿ ӹ .

  ̷ ۾  TCP  Ǵ Transmission Control Protocol̶
  ϴ    ݿ  Ǹ, IP  ֻ ۾Ѵ. TCP
    Ư̶ Ѵٸ,  ȣƮ Ʈ ӽŻ ִ 
   μ ܼ ִ    Ű ϱ  IP
  ϴ ̴. ׷,  ڷᰡ  η ġ  
  ʿ䰡 . TCP   б⵵ ϰ ⵵  ϴ μ
   ٸ  ִ ۼ   Ѵ.  ȭȭ
    ȴ.

  TCP   ȣƮ ϰ ִ IP  ģ   
  ȣƮ ִ ̸ port  ϰ  Ѵ. Ʈ Ʈũ
     ġ    ̴. Ѱ   
   ȭ ų  ִٸ, IP  巹  ڵ ( ,
  ÿ ų  ִ )    ְ, Ʈ ȣ  ڵ
  (,   ȭ ų  ִ )   ִ.

  rlogin   ,  Ŭ̾Ʈ ø̼ (rlogin) erdos
  ִ ϳ Ʈ ְ, quark ִ Ʈ ȣ 513 Ű
  rlogind   ڸ    ˷ ִ.  ̰ TCP
   ȮŲ.  ̷   ؼ, rlogind  
  Ű  Ÿ ȴ.    ǥ Է°  TCP
  Ǿ ִ  ۽Ų.  ׷  迡 rlogin
  Էϰ Ǹ,  Էµ ȣ TCP Ʈ ϰ  ̰, 
  ǥ  Է ޾Ƶ鿩 Ǵ ̴.

  1.3.7.  The User Datagram Protocol

   TCP TCP Ʈŷ  ݷνḸ ϴ 
  ƴϴ.  rlogin   ø̼ǿ  ̶
  ϴ,  װͿ ݵǾ ִ  NFS  ø̼ǿ
   ϴ. ſ, TCP   UDP Ǵ User
  Datagram Protocol Ѵ. TCP  UDP   Ʈ ӽŻ
  ִ  Ʈ 񽺸 ϱ  ϳ ø̼ ϰ
  , ̰   Ȯ  ʴ´. ſ,  ܵ
  Ŷ  񽺿      ִ.

     ߾ NFS  - galoisκ   TEX
  丮  Ʈ Ǿ ְ, LATEX     
   ;Ѵٰ . 켱  ü ͷ о 鿩.
  , galois TCP  Ȯϰ,  , װ ٽ
  ϴ  ʹ  ð ɸ ̴. ſ, galois
    ϳ û , ̰ ѽ UDP Ŷ ִ  
  ̸, ӵ鿡    .  UDP սǵ Ŷ̳
  浹 Ͼ Ŷ  ʴ´.   쿡  
  ø̼δ NFS , ̰ ׷ Ŷ ȣ ش.

  1.3.8.  More on Ports

  Ʈ Ʈũ    Ʈ   ִ.  ϳ
  ø̼  񽺸 ϰ Ѵٸ, װ ϳ Ʈ
   ü Ű, Ŭ̾Ʈ  ٸ. (̰ Ʈ listening
  Ѵٰ θ.)  񽺸 ϱ ϴ  Ŭ ̾Ʈ  
  ȣƮ ϳ Ʈ Ҵϰ, Ʈ ȣƮ  ִ  Ʈ
   Ų.

  Ʈ ߿ Ư߿ ϳδ  Ŭ̾Ʈ  ̿
  ̷,   ٸ 纻  Ʈ Ǹ,  
  Ŭ̾Ʈ  listenѴ. ̸ ׸, ̰ δٰ  Ʈ
  513 ؼ,  ȣƮ  ٸ    ÿ 㰡Ѵ.
  TCP ̷ θ   Ȯ   ִ. ֳϸ, װ͵ 
   ٸ ȣƮ Ʈ ߴ ̱ ̴.   , 
   erdos  quark Ѵٸ, ù °  rlogin Ŭ̾Ʈ
   Ʈ  1023  ̰,   ° Ŭ̾Ʈ Ʈ 1022
   ̴.    ٴ quark Ʈ 513   ̴.

    Ʈ  ϳ Ŭ̾Ʈ Ư 񽺸 
  ؼ Ư  Ʈ ϴ  Ʈ   ִ.
  Ŭ̾Ʈ    Ʈ ȣ ĺϱ ؼ, ̷
  ȣ Ҵ  ִ   ý ڻ̿ ׷  ǰ
  ̷ Ѵ. rlogin  θ Ǵ  񽺸 , ̷
  ȣ   Ǿ Ѵ. ̰ IETF - Internet
  Engineering Task Force    , װ Ҵ ȣ 
  RFC  Ѵ.  ̰ ٸ ͵ ߿ well-known
  services Ҵ Ʈ ȣ Ѵ.   ׷ ȣ 
   /etc/services θ     Ѵ. װ
  The services and proto cols Files (9.3) ڼϰ  ̴.
   TCP  UDP  Ʈ鿡 ϰ ִ  ϴ ̵ ȣ
   浹  Ͼ ʴ´.  ǹ̴ TCP Ʈ 513 UDP Ʈ 513
  ٸٴ ̴. ǻ, ̵ Ʈ   ٸ  , rlogin
  (TCP)  rwho (UDP)    ٸ 񽺸  Ʈ
  Ѵ.

  1.3.9.  The Socket Library

  UNIX  ü,  ۾    ϴ
  Ʈ 밳   Ŀ Ϻκ̴. UNIX 迡
   Ϲ ϴ α  ̽ Berkeley Socket
  Library̴. װ ̸  Ʈ   ÷ ׸ Ⱦ ϴ
  Ͱ  Ʈ Ѵٴ ߿   ̴. װ Ʈ
  ȣƮ   ׸ 񽺸  ϱ  (bind(2)) ȣ
  Ѵ.  ̰   α׷ (using connect(2), listen(2),
  ׸ accept(2)) ϰų   ִ.  ̺귯 ټ
  ̱ , װ  (AF_INET ) ⺻  ϴ
  TCP/IP Ŭ Ӹƴ϶     (AF_UNIX Ŭ) ϴ
  Ŭ Ѵ.   XNS (Xerox Networking System)
   Ǵ X.25     ٸ Ŭ   ó  ִ.

  ,   ̺귯 ǥ libc C ̺귯 Ϻκ̴.
  , װ AF_INET AF_UNIX ϸ , Novell Ʈŷ
      ս Ű  , ħ ϳ ̻ 
  Ŭ սų  ְ Ǿ.

  1.4.  Linux Networking

    α׷ӵ ̷  ̸,  
  Ʈũ ̴   ߴ. ̹ ʱ ܰ迡  
  Ʈũ ȣȯ ۾ ̷ ͵    ͵ ƴϴ. ̹
  ʱ ܰ迡  UUCP  󿡼  ࿡ Ű, 1992 
  Ross Biro ٸ  TCP/IP  ʷ Ʈŷ Ͽ, 
   Net-1 ˷ Ǿ.

  1993 Ross  Ȱ ߴ , Fred van Kempen  Ӱ
  ۾ ϱ Ͽ, ׷ , Net-2  
  Ǿ. 1992   ù    Net-2d  ´. (̰
  0.99.10 Ŀ Ϻκ̴.) ׸    ߿ Alan Cox
  Net-2Debugged ϰ ϰ ־. ɰ ׸ ϰ,
  ڵ忡   ۾ ̷ ķ,  ̸ Net-3
  ٲν  Linux 1.0  ϱ⿡ ̸. 翡  
  Ʈŷ ڵ尡   Ŀ  Ե  ִ.

  Net-3  ϰ ȭϴ ̴  Ӹƴ϶, SLIP (ø
    Ʈũ ), ׸ PLIP (з   Ʈũ
  )  ġ ̹ Ѵ.  ȯ濡   ϴ
  TCP/IP   ִ  Net-3    PC н
  ɰϴ   ð ְ ִ.  ϰ ִ  
  ͳ ȣƮ 󿡼 ְ   ϴ  ǥ ΰ
  Ȱϰ   .

  ̷ ۾  ϰ ִ ν,   Ʈ
  ߿  ,  뼺 ȭϴ  ū  
  ̴. PPP (Point-to-Point Protocol,    ؼ Ʈũ
   ϴ  ٸ )  ̹   Ÿ  迡 ,
  ham radio  AX.25 ̹  ܰ迡  ִ.  Alan Cox
   Novell IPX   ̹ ϰ , 
  Ʈŷ    ȣȯ    , Novell
  IPX        ִ. ֳϸ, ʿ 
  Novell    ־ ̴. 巡   ٸ
  δ,  н  NetBIOS   samba ־, Andrew
  Tridgell    ִ.- NetBIOS lanmanager ۾׷
   ϴ Windows  ø̼ǻ ִ ̴.
  1.4.1.  Different Streaks of Development

   ȿ, Fred Net-2e  ۾  Ͽ,   
   Ʈŷ   ߴ.     ִ   ,
  Net-2e  Ÿ  Ʈ.  Net-2e  ָ 
  ̶, DDI,Device  Driver Interface  պ  .  DDI
  ׻    Ʈŷ ġ   
  Ͽ.

  Linux FreeBSD  ISDN  Matthias Urlichs  ٸ
  TCP/IP  Ʈŷ  Ͽ.  ۾  ״  BSD Ʈŷ
  ڵ带 Linux Ŀο  ״.

  ׷ ̷    ־  Net-3 ״  ӹ ־.
   Alan ham radio amateurs ϴ AX.25   ۾
  ϰ ִ. ǽ    Ŀ  "module"̶ ڵ带
  Ͽ Ʈŷ  ڵ忡 ο Ȱ Ҿ   ־. Modules
   Ŀ ð ̹ ߰  ְԲ ش.

  Ʈũ ϴ  ٸ     񽺸
  ϱ   ߴ. ׷ Ŀΰ ġ  ̿ ֿ
   ־. ׷, е Net-2d Ǵ Net-3, ׸ vice
  versaκ  ƿƼ  Net-2e Ŀ ۽Ű  ý
     ̴. ̰  Ŀ  θ ٷ  
   ̸,  ø̼̳ rlogin Ǵ telnet  Ϲ
  Ʈŷ ɿ   .

  ׷, ̷  Ʈũ    
  ųŭ Ÿ ƴϴ.   Ȱ 
  ʴ,  ϴ TCP/IP  ڵ忡   ʿ 
  ̴.  Ŀ  ׻ Ŀο ǥϴ Ʈŷ ڵ ȣ
  ȯϴ Ʈŷ   ̴.

  1.4.2.  Where to Get the Code

   Ʈũ ڵ ֽ   anonymous FTP ϴ  
  Ʈ   ִ. Net3   FTP Ʈ
  sun.site.unc.edu Ʈ system/Network/sunacm ̷Ǿ ִ
  sunacm.swan.ac.uk̴.  Net-2e ֽ ġ  ŰƮ ̳ʸ
  ftp.aris.com ãƺ  ִ.  Matthias Urlichs' BSD-derived
  Ʈŷ ڵ ftp.ira.uka.de /pub/system/linux/netbsd濡 
   ִ.

  ֽ Ŀ uic.funet.fi/pub/OS/Linux/PEOPLE/Linux ã  
  ִ.; sunsite tsx-11.mit.eduƮ  丮 ̷ Ҵ.

  1.5.  Maintaining Your System

   å ؼ, 츮 ַ ġ    ٷ ̸,
  Ư     ٷ ̴. - 񽺸  Ŀ,
   ۾    Ѵ.  ׷ п mail
  news   񽺵 ʿϰ  ɰ̸,  ý ֽŽ
  ϱ  ƾ ۾  ʿ䰡 ְ ȴ.  忡 ̷
  ۾  ڼϰ ٷ .

   ³ ġ  ϵ Ͽ ø̼ α ϰ
  ý ˻ϴ  ý Ű  ּ ۾̴.
  Ϲ,   밳, ̷   ϱ ,     
  ũƮ ۼؼ, ̰͵  cron ׸ ־ ΰ  
  ϰ ; ̴. smail  C  News   ֿ  
  ø̼ ҽ  ־ ׷ ũƮ  ԽŰ ִ.
   ʿ   ,  ϴ   ľؼ,
  ũƮ ۼؾ Ѵ.

  cron ۾     ۵ȴ. 
  ø̼ǵ  , 뷮 Ǵ root  ϴ
  α   ̴.   root   α
  Ѵٸ, ̰   ΰ ̴. ;    
  root  ϱ ؼ 14忡 ϰԵ mail alias
  ϴ ͵    ̴.

     Ʈ Ǳ ؾ Ѵ. Murphy's
  law ǥȭ    ش. ׷Ƿ, ý
  Ųٴ  ׷ Ÿ   ְ ٴ ǹ̴. 밳
   ý ڰ  root   ؼ, email 
  Ѵٰ ϰ ,   鿡 Ȯϰ å 
    ϱ  Ϲ ϴ  ٸ ּҰ ִ.
  ̸׸, ۵Ҵ      ϴ  밳
  postmaster ּȭ Ǿ ִ.  ;  news ý      Ÿ
  newsmaster   ̳  usenet        𸥴.  hostmaster
   ߼۵Ǵ  ȣƮ ⺻ Ʈũ 񽺿    
     ִٸ, DNS  񽺸 ϰ ִ 
  ۵Ǿ Ѵ.

  1.5.1.  System Security

  Ʈũ ȯ濡 ־ ý    ٸ ߿ ۾δ
  ħڷκ   ý۰ ڸ ȣϴ ̴. ϰ
  ý ϴ   鿡 ǥ ϴ Ͱ
  ̴. ; н带 ϴ Ϳ Ethern et Ÿ
     ٿִ   ʷ ̸,   ޽
    սǱ Ǵ  Ȱ ħؿ   Ű
  ȴ. 츮 װ  ߻  ִ  ϸ鼭, ׷
  Ư    ذ  ̴.

    ý  ٷ ⺻  ׿    
   ̴.  ,  ȭ  ϰ   
   ٷ . ;  Ͼ  ִ  ٷ̴.
  ׷, ȿ õǾ ִ  å д    ߿ ϸ, װ
  ý Ʈũ ÷ ؼ ʼ̴.  Simon Garfinkel
  "Practical UNIX Security" ([Spaf93] ϶.)   õ  
   å̴.

  ý   ý ϱ ۵Ǿ. ̰  ߿
   ϰ  丮 ǰ 㰡 ˻ϰ, Ưϰ ϴ
   ¸ Ȯϴ ۾ ϰ ִ. ̸׸, COPS
  α׷ 幮 㰡 Ǵ  ٸ  Ȳ ,
  Ͻý۰ Ϲ  ϵ ˻ ̴. ׸ 
  н带   Ư Ģ  ϱ   ͵ 
  ̴. ̸׸,     ټ  ڸ 
  н带 ʿ  Ѵ.  н忡  ڿ ȣ ϰ
  ִ.

  2.  Issues of TCP/IP Networking

   忡   ӽ TCP/IP  Ʈũ   ,
  εġ  λ ׵ IP 巹, ȣƮ ,  
   ˾ƺ.  ׸, ʿ ۾   ϱ ؼ ˾ƾ
  Ǵ ⺻ , ̷ ۾ ʿ  ٷ
   .

  2.1.  Networking Interfaces

  Ʈŷ ȯ濡 Ǵ  پ缺 ߱ ؼ, TCP/IP
  ϵ     ϳ ߻ interface  ΰ
  ִ.  ̽   ڸ Ѵ.  ׸, װ 
   ϵ   · ΰ, Ŷ  ޴ ۾   .

  Ʈũ Ǵ  ֺġ ׿  شϴ ̽ Ŀο
  ǥõǾ  ־  Ѵ.     ,    ϴ  Ethernet
  ̽  eth0  ׸, eth1  ǥõǾ ְ, SLIP ̽
  sl0, sl1  ǥõǾ ִ.  ̵ ̽ ̸ 
  Ŀο Ư  ġ ̸ ű  ,  
  Ѵ. װ͵  Ư ǹ̸  ִ  ƴϴ.

  TCP/IP Ʈŷ  ϰ ϱ ؼ,  ϳ IP 巹
  ϳ ̽  Ҵؾ Ѵ. IP 巹 迡  
  , ڽ  ź ִ    ȴ.  巹
    ̽ ̸ ٸ.  ;    
    Ѵٸ, 巹   پ ִ п .

   ؾ ϴ  ٸ ġ μ ִ. ̰͵ ϳν
   ׷   ũ⸦ ϴ κ  ִ. ̰  ϵ
  Ư κе  ó   ִ.  ̰ MTU Ǵ Maximum Transfer
  Unit θ.  ٸ Ӽ  Ұϱ .

  2.2.  IP Addresses

  1 忡 Ѵ, IP Ʈŷ     ִ
  巹 32Ʈ̴.  Ʈ ŷ ȯ濡 ִ     
   Ҵ   ִ.    ٸ Ʈ ũ TCP/IP
  ȯ ̷  ʴ Ϲ   Ʈũ  ϰ ִٸ, 
    ⿡  ̵ ȣ Ҵ   ̴. ׷,
  ͳݿ ִ    Ʈ ߾ӱ , NIC - Network Information
  Center - 밳, ι̴ п IP address Ҵϸ,
    װ Ѵ. Ǵ е ϴ IP address 
  NIC ؼ   ִ.  ּҴ  .
  hostmaster@internic.net   ȣ Ҵ  ̴.

  IP address  б ؼ, octet θ   8Ʈ 
   Ҵ.   , 0x954C0C04 IP address 
  quark.physics.groucho.edu  149.76.12.4  ִ. ̷
  ¸ dotted quad notation̶ θ.

   ǥ   ٸ ν, IP address    network
  ڷ,    host ڷ   ִ.   NIC
  IP address û ,  ȹ  Ҵ  ʴ´.
  ſ,  ϳ Ʈũ ڸ ޾Ҵٸ,  Ʈũ 
    ȣ ,  ȿ IP address Ҵ 
  ִ.

  ȣƮ κ Ʈũ Ը ϱ   ۾ų,
  ũԵ  ʿ䰡 ִ.      ʿ伺 ֱ 
  Ʈũ    Ŭ , ̰     IP
  address   ִ.

     Class A
        Class A 1.0.0.0 127.0.0.0 Ʈũ ϰ ִ.
         Ʈũ ڴ ù ° ݿ ԵǾ  ִ.  ׸ ̰
        24 Ʈ  ȣƮ κ , 뷫 160  ȣƮ  
        ִ.

     Class B
        Class B 128.0.0.0 191.255.0.0  Ʈũ ϰ
         .  ; Ʈũ ڴ ù  ݿ ԵǾ  ִ.  ׸
        ̰ 16320 Ʈũ ϰ ,  65024
        ȣƮ  ִ.

     Class C
        Class B 192.0.0.0  223.255.255.0 Ʈũ ϰ
        ִ.  Ʈũ ڴ ù  ݿ ԵǾ ִ. ׸ ̰
         2鸸 Ʈũ ϰ , ְ 254 ȣƮ
          ִ.

     Class D, E, and F
        224.0.0.0 254.0.0.0  ִ ּҵ ̰ų
        ̷  Ǿ ֱ ,  Ʈũ 
        ʴ´.

  1忡    ٸ,quark  ּ 149.76.12.4 Class B
  ش  Ʈũ 149.76.0.0 ȣƮ 12.4 ٰ   ִ.

  ּ  ۿ  ȣƮ κп ִ    
     ´ٴ  ¼ ˾    𸥴.
  ֳϸ,  0,    255  ȣƮ ڵ Ư 
   ̹ Ǿ ֱ ̴.  ȣƮ κп ִ ּ Ʈ
   0ΰ Ʈũ Ÿ,   κ  1  εĳƮ
  ּҶ  θ, ̰ Ʈũ õǾ ִ   ȣƮ
  Ÿ.  ׷, 149.76.255.255   ִ ȣƮ ּҰ
  ƴ϶, Ʈũ 149.76.0.0 ִ  ȣƮ Ÿ.

  Ư Ǿ ִ   Ʈũ ּ , 0.0.0.0 127.0.0.0
  ִ.  ù ° ּҴ ٸ  default route θ,   
  loopback address θ.  Ʈ Ʈ IP   
    ϰ ,     ̴.

  Network 127.0.0.0 is reserved for IP traffic local to your host.
   κ 밳, 巹 127.0.0.1  ȣƮ loopback
  interface θ Ư  ̽ Ҵ ̸, װ ġ
  ȸο  ۵Ѵ. TCP Ǵ UDP ǳʿ IP Ŷ ġ
   Ʈũ ǰ ִ Ͱ   ̽ ǵ
  ̴. ̷    Ʈũ   ʰ
  Ʈŷ Ʈ  ϰ   ִ.  
  ȣƮ󿡼 Ʈŷ Ʈ ϰ   , ϰ  
   ִ  ٸ ø̼ ִ.  ̰  Ư ͸ ƴϴ.
  ̸׸,  UUCP Ʈ IP    ƴ,
  ׷ ұϰ,  INN  ý ϰ ;Ѵ.
     ҷ, INN  ̽ ʿ
  Ѵ.

  2.3.  Address Resolution

    IP address    ƿԴ.
   װ͵  ٸ ȣƮ ִ Ethernet󿡼 
  Ǵ ñ  𸥴. ᱹ, Ethernet    
  ݼڷ ȣƮ ϴµ, װ  Ϲ ϳ IP address
    ƴϴ. ׷ ?

  ׷. װ Ethernet address IP address Ű 
  ī ʿ   ̴. ̰ ٸ, Address Resolution
  Protocol Ǵ ARP θ. ARP Ethernet   ,
  ham radio   ٸ  Ʈũ ȴ. ARP  
  ʸ ΰ ִ μ, 150 ߼ӿ Mr.  X. Ample ãƾ
   , κ     ұ? ;  ѷ 鼭 
  ̸ θ, װ  ̴.

  ARP ־ IP address ġϴ Ethernet address ã  ,
  Ethernet Ư¡  ϳ "εĳ" Ѵ. װ
  Ʈũ  ִ    ڷḦ ÿ  ̴. ARP
   εĳƮ ڷ IP address  ϳ Ǹ  ϰ
  ִ.   ڷḦ ޴  ȣƮ  ü IP address   װ
  ؼ,  װ ġ Ѵٸ, ȸ ȣƮ   ARP
  .  ȸ ȣƮ    ۽ Ether net address
  ˾Ƴ  ִ.

    迡  ִ   Ethernet  ȣƮ
   ã,    Ethernet̾ ϴ ñ ̴.  ̷
  ӿ ̶     ϰ ȴ. , 
  Ʈũ ִ ȣƮ  ġ ˾Ƴ ̴. ̰  
  ؼ   ڼϰ ٷ ̴.

  񵿾, ARP  ̾߱ α . Ѷ, ȣƮ Ethernet
  address ߰  , װ ARP ĳ ߴ.  ׷,  
  ڷḦ ȣƮ    , װ  Ǵ  
  ʾҴ. ƹ ׷ϴ,     ϰ ϴ  
    ̴. ̸׸,     Ʈ ȣƮ
  Ethernet ī     ִ. ׷, ARP ״   
  Ǿ.  IP address    ٸ Ǹ س ؼ, ARP
  ĳ ִ ü   ȴ.

  , ־ Ethernet address õǾ ִ IP  address
  ߰ϴ ͵ ʿϴ.    Ʈ 谡 Ʈũ ִ
  κ  Ʈϰ   쿡 ߻Ѵ.   ̷ 
   幰 ʴ. ׷ Ʈ Ŭ̾Ʈ  
  ü          ʴ.  - Ethernet  address
  ϰ!  So what  it basically does is broadcast a message
  containing a plea for boot servers to tell it its IP address. ̰
    ٸ  , Reverse Address Resolution Protocol Ǵ
  RARP ִ. BOOTP ݰ Բ, ̰ Ʈũ   ũ
  Ŭ Ʈ ƮƮϱ     Ѵ.

  2.4.  IP Routing

  2.4.1.  IP Networks

      , 밳   ,
  (), ȣ   ,   ּҸ  ̴.  װ
  Կ ,  ϴ ü    װ  ּҷ
   ̴; װ   õǾ ִ  Ǵ () 
    ̴. ׷, װ ִ  ü    
   ̴.     иϴ;    
  𿡼 ġ,     ü  ( )  
  뷫  ̴. ׷,   ּҷ    ʿ
     ̴.

  IP Ʈũ ̿  · Ǿִ.  ü ͳ automonous
  systems  Ҹ    Ʈũ ̷  ִ.   ý
      ȣƮ̿   Ѵ. ׷, 
  ȣƮ Ʈũ  θ ߰ν, ͱ׷  ϴ
  ۾     ִ. ̰  ׷ Ư  Ʈũ
  ִ  ȣ Ʈ Ű ,  Ʈũ  ü ؼ,
  װ óѴٴ ǹ̸  ִ.

  2.4.2.  Subnetworks

    Ͱ , IP  address ȣƮ κа Ʈũ κ
  ν,   Ÿ  ִ.  Ʈũ IP address
  Ʈũ κп  ̴. ׷,   IP Ʈũ ȣ
   ȣƮ  Ʈũ ߰ߵȴ. -  Autonomous ý۵ 
  ݴ Ϲ̴. װ͵  IP Ʈũ   𸥴.

  װ 鰳   Ʈũ հ Ethernet   
  Ʈũ ̷     ̷ ķδ, Ʈũ
  inside ϴ  Ű  ϴ ͵ ġ ´ ̴.
  ׷Ƿ, IP  ϳ IP Ʈũ ȭǰ, װ 
  subnet .

  IP Ʈũ κп Ư IP address   ׷  ϴ
   ϳ IP    ð ִ. Ŭ A, B, Ǵ C 
  װ͵ IP address  Ʈũ κ ȭ εǾ . ׷ 򿡴
  ȣƮ κп  Ʈ  ԽŴν, Ʈũ κ ȮŲ .
    ȣ ؼǴ Ʈ ȣ subnet mask Ǵ netmask
    .  ̰ 32 Ʈ ̷ ڵ̸, IP address
  Ʈũ κ  Ʈ ũ ǥѴ.

                        Figure 2.1: Subnetting a class B network

  ׷ Ʈũ  ν, Groucho Marx University Ʈũ 
   ִ. װ Ŭ  B شϴ Ʈũ ȣ 149.76.0.0
  , װ  Ʈ 255.255.0.0 ȴ.

   GMU  Ʈũ   Ʈũ ̷
  ִ.  ׷, IP    254  , 149.76.1.0
  149.76.254.0 صǾ.   , Theoretical Physics δ
  149.76.12.0 ҴǾ. ׸ campus backbone ü
  Ʈũ , 149.76.1.0 Ҵ޾Ҵ.  ̷ ݵ  IP
  Ʈũ ȣ ϰ ִ. ݸ鿡  °  װ͵ ̿
  еǾ ȴ. ׸Ͽ װ͵ 255.255.255.0̶ ϳ 
  ũ  ̴.

  ׸ 2.1 quark ּ 149.76.12.4   ؼǴ
  ش.   ּҰ  Ŭ B Ʈũ ϰ Ǵ ,
    ϴ ش.

   (      ̷Ե θ.)   
  Ʈũ  internal division μ ġִ  ƴϴ. 
  Ʈũ ڰ   ϰ  Ǵµ,    ϴ 踦
  Ÿ    . װ͵  (ΰ Ethernet
  ̿ )̰,  ( department̿) ̸,  ̸,
  ̷  ݵ ɰϴ     鿡 ־. 
     Ʈũ   Ȱ  ĥ   ,
  ٱ 迡   Ÿ ʴ´.

  2.4.3.  Gateways

   ν,      ƴϴ. װ 
  ϵ  Ѱ ߿伺  츮 νĽ ֱ⵵ Ѵ. Ethernet
     Ʈũ ִ ȣƮ   ٸ, ſ ѵǾ
  ִ.  ѻ̶      ִ ȣƮ 
  ش Ʈũ ־ Ѵٴ ̴. ٸ   ȣƮ
  gateways       ִ. Ʈ̴  ̻
    Ʈũ ÿ Ǿ ִ ϳ ȣ Ʈ̴. ׸
  װ װ͵ ̿ Ŷ ȯϴ ۾  ش.

   ȣƮ   Ʈũ ִٸ, IP  νĽŰ
  ؼ,  ٸ   Ʈũ  ٸ IP Ʈũ  ־
  Ѵ.  , Ʈũ ȣ 149.76.4.0 mathematics LAN ִ
  ȣƮ Ǿ ִ ,    ׷  quark  
  , erdos ִ Ʈũ Ʈ  IP address,
  149.76.12.4 Ÿ ش. ׸,  ڷ Ʈ
  (ʱⰪδ sophus Ǿ ִ.) ļ,  ȣƮ 
  ̴.

  sophus  ü    ٸ ݿ Ǿ ִ. :
  Mathematics Department, ׸ campus backbone. װ eth0
  fddi0 ϴ  ٸ ̽ ļ Ѵ.   ,
  츮 Ҵ IP  address  ?  ׸  149.76.1.0 Ǵ
  149.76.1.4  ߿  װ Ҵ  ־  ?

   Ѵ̴. Maths LAN ִ ȣƮ  ϰ  , sophus
  IP address 149.76.4.1 ؾ ϰ, 麻 ִ ȣƮ 
  ϰ  쿡 149.76.1.4 ؾ Ѵ.

  ׸Ͽ, Ʈ̴ Ʈũ ϳ  IP address Ҵ޴´.
  ̷ address  شϴ ̽ ġǾ ,
  Ʈ̸  ļ, ݿ  ȴ.  ǥ  sophus
  ġϴ ̽ 巹 ְ ִ.

   ̴ ü  ̽ lo̴.  ̰ 2.2
  Ұ Ǿ .

  ׸ 2.2 Groucho Marx University (GMU) ִ Ʈũ 
  ܸ ְ ִ.   ݿ ִ ȣƮ 
  ִ address ְ ִ.

             Figure 2.2: A part of the net topology at Groucho Marx Univ.

  Ϲ,  ȣƮ ̽ 巹 ߰Ű
         . erdos  ϳ
  Ʈũ  ִ ȣƮ  , i    ̰
  IP address  ִ ȣƮ ȸ  ̴.  , 
  Ʈ̸  ,   ſ ߿ ۿ   ִ.

  2.4.4.  The Routing Table

  ⼭  ׷ Ʈ  Ʈũ Ѱ ,   IP
   Ʈ̸     ̴.

  quark  ׷  , erdos  ּҸ ˻ϰ, 
  Ʈũ  װ  ϴ ȮϿ.  ۾ erdos
  Ʈ Ʈ sophus  ڷḦ    ۾    ƶ̶
      ִ.  sophus quark  Ʈũ͵  Ǿ
    ʴٴ  νѴ. ׷, sophus   ġ  ٸ
  Ʈ̸ ãƳ  ̴. Ȯϰ ߴٸ, װ Physics
  Department  Ʈ niels ̴. sophus 
  Ʈ̸   Ʈũ ϱ    ʿ
  ϰ ȴ.

  ̰ ϴ   IP ⺻ Ʈ̿ Ǿ
  ִ Ʈũ    ǹѴ. Ϲ ٸ  ü
  ؾ ϸ,  ̰ Ʈũ 0.0.0.0 õǾ ִ
  Ʈ̴. ˷  Ʈũ   Ŷ Ʈ
  Ʈ ļ  ȴ. sophus󿡼,  ̺  
   ̴.

  sophus  Ǿ ִ Ʈũ Ʈ
  Ʈ̸  ʿ   ´. ̷  Ʈ ü
  "-" ǥõǾ ִ.

   ̺   ǹ̷ ؼ  ִ. Ը  LAN
  ؼ Ʈð    route ɾ Էؼ װ͵
  IP ǵϰ, ϴ   ȿ  . (5  ϶).
  ̰ͺ     ū Ʈũ   ؼ ð routing
  daemons  ־ Ѵ. ̰͵ Ʈũ  ߾ ȣƮ
  Ǹ,  Ʈũ ̿  Ʈ  ֱ ؼ 
   ȯ ̴.

  Ʈũ Ը ϴ   ٸ      ̴.
  Groucho Marx campus  ڹ ýۿ  ϱ ؼ
  internal routing  protocols  Ѵ.  ε巯 ϴ 
  ϳ ٷ RIP, Routing Information Protocol ̸, װ BSD routed
    ȴ. ڹ ýۿ  ϱ ؼ EGP
  (Ext ernal Gateway Protocol) Ǵ BGP  (Border Gateway Protocol) 
   external routing   protocols ؾ   Ѵ. RIP   Ӹ ƴ϶
  ̷  ͵鵵 Cornell's  gated   ǰ ִ. -
    routed Ҿϴٰ  Ѵ.  gated RIP ϴ
  ķδ routedſ gated ϴ   .

  2.4.5.  Metric Values

  RIP ⺻ ϰ ִ     ȣƮ "hops"
  ȣ  ʸ ΰ ִ Ʈũ  ְ Ʈ Ѵ.
  ׸   ׷  ϱ  Ʈ ̸ ľ Ѵ. ܰŸ
  Ʈ RIP ۷  . 16̻ ȩ( ο 
  ϴ ϳ ) ġ Ÿ Ʈ   
  ֵǸ,  óȴ. ٽ    ȵȴٴ ǹ̴.

    Ʈũ ִ   ϰ, RIP ϱ
  ؼ  ȣ  Ʈ gated Ѿ Ѵ. Ʈð gated
  Ʈũ  ̽ Ͼ   Ȱ  ˻Ѵ. Ȱϰ
  ִ ̽ ϳ ̶̻ (⼭  ̽ 
   ʴ´.) ȣƮ  Ʈũ ̿  Ŷ  
  Ȱ ȯϰ  ٰ   ִ. ׷ ʴٸ,  ٽø
  Ȱϰ ִ ̽ ٸ, RIP  ֽ  ްų 
   ̺ ϴ ۾ ұ  ̷ ִٰ  
  ִ.

    ̺κ   , gated  ̺
  Ʈ õǾ   metric value  Ʈ ̸ Ѵ.
  Ʈ   , ý ڰ  Ͱ   ϸ, 
  Ʈ ϴ     ƾ Ѵ. ׷Ƿ
  ȣƮ   Ǿ ִ  Ͱ ׻  0 Ǿ
  Ѵ. ݸ鿡,   Ʈ ̸ ġ ϳ Ʈ Ͱ
  ڸ Ǿ Ѵ.  ,  RIP gated   
   Ͱ ؼ  ʾƵ ȴ.

  2.5.  The Internet Control Message Protocol

  IP 츮    companion protocol  ִ.
  ̰ ٸƴ Internet Control Message Protocol (ICMP) ̸, ٸ
  ȣƮ ޽  ߻ϴ  ȯϱ  Ŀ Ʈŷ
  ڵ带 Ѵ. ̸׸,   erdos ְ, quark ִ
  12345 Ʈ  ϰ ϸ,  Ʈ  μ
  listening  ʰ ִٰ Ѵ.  Ʈ  ù ° TCP
  Ŷ quark  , TCP Ʈŷ  Ŷ ν
  ̰,  "Port Unreachable"  ICMP ޽ erdos ǵ 
  ̴.

    ִ ICMP ޽   ,  ߿  ¸
  ϴ ޽ ִ.  ߿ Redirect message Ҹ ſ
  ̷ο ޽ ϳ ִ.    ª ΰ ִϴ,
  װ  ⿡  Ǹ, ٸ ȣƮ Ʈ̸ ؼ
  װ   ȴ.  ,  Ŀ sophus 
  ̺ ҿ °   ְ, Mathematics Ʈũ FDDI
  麻 ΰ ԵǾ   , Groucho Computing Center's
  gateway (gccl) ִ Ʈ  ʱⰪ Ǿ  
  ִ. ׷ quark ִ Ŷ Physics Department ִ
  Ʈ niels  gccl  ̴.   
     ׷ ۹ , gccl  Ŷ niels
  ٽ Ұ̰, ÿ ֻ   ϴ ICMP Redirect
  ޽ sophus  ̴.

  ϰԵ   ⺻ ۾  ؾϴ
  ŷο ϱ     ó ϼ  RIP  ICMP
  Redirect messages      ϰ ִϴ ̰
  ׻    ƴϴ. ICMP  Redirect  RIP   
       ϱ   û׵ 
   ʴ´. ̰ Ȥ   ü Ʈũ Ʈ пŰ
   Ƿ   ۾ ϰ ִ  . ̷ 
  , װ͵ ġ ȣƮ θ   ߼ϴ ó, Ʈũ 
  Ʈ  ġ Redirect messages ġϱ   Linux
  Ʈŷ ڵ尡 ִ.

  2.6.  The Domain Name System

  2.6.1.  Hostname Resolution

    , TCP/IP Ʈŷ 巹  32Ʈ ڵ
  ȴ. ,  е  ڵ ϴµ   
   ̴. ׷, ȣƮ  Ϲ gauss Ǵ strange 
   ̸  ִ.  ̸ ġϴ IP 巹 ã  
   ø̼ ǹ̴. ̷  host name resolution̶
  θ.

  ־ ȣƮ IP 巹 ãƾ ϴ ø̼ ȣƮ
  IP 巹 ã   ü  ü踦    ʴ.
  Instead, it relies on number of library functions that do this
  transparently, called gethostbyname(3) and gethostbyaddr(3).
  , ̷ ͵   Ǿ ִ ڴ resolver
  library ϴ  ̺귯 ׷ȭǾ ִ;  󿡼
  ̷ ͵ ǥ libc  κ̴. ϻ, ɵ 
  "the resolver" θ.

   Ethernet  ׸ Ʈũ  װ͵
  ŬͿ ȣƮ  巹 ԽŰ ̺ ϱ
    ۾̴. ̷  밳  ϸ  /etc/hosts
  ϴ  ǰ ִ. ȣƮ ߰ϰų  , Ǵ
  巹 ȯ ,   ȣƮ ִ hosts 
  ־  .  и ̰  ǻͷ Ʈũ ϴ
  ͺ   ۾ 𸥴.

  Sun Microsystems  NIS, Network  Information System ̷
   ذϱ  ϳ  YP , ο    
  Ҵ. NIS  ȣƮ ִ  ̽ hosts ϰ 
  ٸ   ´. ׷ Ŭ̾Ʈ ʿ    
   ̽ ˻  ִ. ̷   LAN  ߱
  Ʈũ   ̴. ֳϸ, ü hosts  ̽
  ϰ, װ   й ־ ϱ ̴.

  ͳ 󿡼, 巹  ⺻  HOSTS.TXT ϴ
  ͺ̽ Ǿ ִ.   Network Information Center
  Ǵ NIC   ǰ ,      Ʈ ۵ǰ
  ġǾ Ѵ.  Ʈũ ؼ  , ̷  
    ߻Ѵ. Դٰ  ν, 
  HOSTS.TXT ġ ؾ ϰ,     йؾ
  ϴ   ϰ ִ.  NIC  Ǿ ϴ 
  ̸ ɰ  ߻  , ̸   
    Ǵ Ȯ ⵵ ؾ Ѵ.

  1984, ̷ ν, ο  ̸ ذ   , Domain Name
  System̶  ä Ǿ. DNS Paul Mockapetris Ͽ,
  ׿ ÿ ּҿ õ   ذ ߴ.

  2.6.2.  Enter DNS

  DNS ΰ ȣƮ  ϰ  ִ.  
  ǹ̿  Ǿ ִ Ʈ ̴. --   Ʈũ
   (  п ִ    , Ǵ BITNET ִ 
  ȣƮ) Ǿ ֱ⵵ ϰ, Ư ⱸ (̱ )  Ǵ   
   ֱ⵵ ϴ. ̸ ׸, е edu  ׷ȭǾ ְ,
   մа ܰ ٽ װ͵ ȣƮ ϰ ִ 
  subdomain Ѵ. Groucho Marx University groucho.edu  
  ο޾ ̰, Mathematics Department  LAN maths.groucho.edu
  Ҵ޾ ̴.  ι Ʈũ ִ ȣƮ  ü
  ȣƮ θ  ̴; ׷ erdos
  erdos.maths.groucho.edu ˷ ִ°  𸥴.  ̰ fully
  qualified domain name Ǵ FQDN̶ θ, ̰  Ư
  ȣƮ 迡  ϰ   ִ.

                            Figure 2.3: A part of the domain name space

  ׸ 2.3    ְ ִ.  Ʈ Ʈ ִ
  ü ϳ -Ʈ- (̰ root domain̶ θ.)  ǥѴ.
  ׸ ٸ      ϰ ִ. ȣƮ  
  ǹ̸   θ ϱ   fully qualified
  domain name ǥϱ ,  װ trailing dot .
  ̰  ̸  Ұ Ʈ ̶  ǹѴ.

  ̸ ü ϰ ִ ϳ   top-level,  second-level,
  Ǵ  third-level  θ⵵ Ѵ. ׸  
  ȭǰ , ׷   ƴϴ.     
  ִ top-level   Ҵ.

     edu
        (밳 ̱ ) ,  : 

     com
        ü  : ȸ(company)

     org
         ü.  UUCP Ʈũ    Ѵ.

     net
        Ʈ̿ Ʈũ   ϴ ȣƮ

     mil
        ̱ 漺 ⱸ

     gov
        ̱  

     uucp
         ξ UUCP ̸ ϴ   Ʈ 
             ϰ Ǿ.

  ͳݿ     (edu, net, mil, gov) ̱
    ְ ϰ  ̱   󿡼 ̵
   ϴ 찡 ִ.   Ưϰ, net  
  , mill gov  ̱   ִ.

  ̱ ̿ 󿡼 Ϲ ISO-3166 ǵǾ ִ  
  ڷ   top-level  Ÿ. ̸׸, ʶ fi
   ϰ,  fr,  de, ׸ ȣִ au top-
  level  Ѵ. top-level   ȣƮ 
   NIC Ӱ   ִ.  , ȣֿ second-
  level   ϴ top-level ΰ ϰ ,
  com.au Ǵ edu.auó   ִ. ϰ  󿡼 Ư
   Ἥ Ư ⱸ  ϱ  ణ   
  ϱ⵵ Ѵ.  , ftp.information.unierlangen.de
  <ftp://ftp.information.unierlangen.de>   ȣƮ ϴ
    幮 ͸ ƴϴ. ϰ  ɷִ 󿡼 
  ϴ ȣƮ  ٸ  ϱ⵵ Ѵ.

  , ̷   Ʒ ϰԵ ȣƮ ǹϴ
    ƴϴ.       ġϰ ִ;  
   ȣƮ   NIC   ϽŰ  ִ.   ȸ簡
  ȣֿ  縦    ,   翡 ִ    ȣƮ ׵
  top-level  se  ϽŲ.

  ,   ִ    ϰ Ǹ, 
  ̸ ߺǴ    ذ  ִ. ; DNS ȣƮ
  ̸ 迡  ϳ̾ Ѵ.  Դ , fully qualified
  name ϱ  Ѵ. ׸  ̹ Ŵ ϳ   
         ִ.

  ׸ DNS  ڸ ļ ؾϴ ۾ , 굵
    ִ   п ִ  ͺ      㰡
  ֱ⵵  Ѵ.   , Groucho Computing Center ִ
  (maintainer)   (department)     
   ִ.  ̹  maths physics 굵 Ҵ.  
  Physics Department ִ Ʈ ũ â · ߰ ȴٸ,
   Ʈũ  ڿ physics.groucho.edu    ϰԲ
   𸥴. ¼    ׵ ϴ ȣƮ 
     , ࿡  Ʈũ    , ܺ 
    ¿  IP ּҸ Ҵ  ִ.

  ̷ Ͼ  ִ  ,   zone
   Ǹ,     ϳ  Ѹ   
  ̴. ⼭  zone domain̿  ΰ ̰ ִٴ 
  ϶;   domain groucho.edu Groucho  Marx University ִ 
  ȣƮ ѷΰ ִ ݸ鿡 zone groucho.edu Computing Center
     ϴ ȣƮ     к   (Mathematics
  Department)   ϰ  ִ.   Physics Department ִ
  ȣƮ ٸ  zone ,  physics.groucho.edu   ִ. ׸
  2.3, ϳ zone    ǥõǾ ְ,  
  ʿ  ִ.

  2.6.3.  Name Lookups with DNS

   Ƽ ̷  ΰ (zone)    ۾
   ϳ ذ ó δ. ᱹ, ȣƮ Ҵ  ִ ߽
    ٸ,    ø̼ ̶  ȴٰ 
   ְڴ°?

   DNS   ҹϰ  亯   ִ.   
  erdos IP ּ  ã ʹٸ, DNS װ ϰ  ִ 
     ̴. ׷     ˰ ; ϴ
   ˷ ̴.

  , DNS Ŵϰ Ǿ ִ ͺ̴̽.  ̰ 
   ǹ̷ν   Ǵµ ־ ΰ  տ  
  Ѵ.   (zone) ؼ,       ,
       (zone) ִ ȣƮ    
  ִ. erdos IP ּҸ ϱ ؼ,  groucho.edu zone 
      ,     Ѵ.

   ϴ ͺ ¼    𸥴.   Groucho
  Marx University        ִ°? ,
   ǻͰ address-resolving oracle   ߾  
  쿡 DNS  ׷   ش.   ø̼
  erdos    ãƳ  ,  Ӽ  ؼ,
  ̸ interative query  Ѵ.   Ӽ Ʈ
    Ӽ Ǹ ν ۾   ϰ ȴ.
  ׸ װ   Ӽ erdos.maths.groucho.edu ּҸ
  ûѴ.  Ʈ Ӽ  ̸ Ʈѿ  ʴ´ٴ 
  νϰ Ǹ,  edu      ִٰ ǴѴ.
  ׷, Ʈ Ӽ  ڼ  ˰ ʹٸ, edu zone
  Ӽ ϶  ̸, ׵ ּҿ Բ  edu
  Ӽ   Ѵ.  ׷,     edu 
   ϳ, ̸׸ a.isi.edu    Եȴ. Ʈ 
    ν, a.isi.edu groucho.edu ִ   
   , п   ִ ġ  ش. ׷ 
     erdos    Ǹ,  װ 
  ּҰ ִ  ˾ ǰ, ġϴ  IP ּҸ 
  ø̼  ȴ.

  ݱ  Ϳ , ܼϰ IP ּҸ  ãµ û
   Ʈ ɸ  ó δ.  HOSTS.TXT Ե
  û    д ͺٴ   ۾̴. ׷
  ̷ ӿ Ǿ    ִ.

  ̷ Ǹ ϴµ  ð ̱ ,  Ӽ 
  cacheٰ     ̴. ׷    
  Ʈũ   groucho.edu ִ ȣƮ ּҸ ã 
  ,   Ӽ ü    ٽ ġ ʰ 
   groucho.edu ϰ   ̴. -   ׷ ʴٸ,  DNS
  ٸ Ͱ    𸥴. ֳϸ,  ǰ Ʈ 
   ʿ ϱ ̴.

  , Ӽ    ϰ   ̴. 
  ణ Ⱓ   , װ  ó ̴. ̷ ð
  time to live Ǵ TTL̶   .     å ڰ
  DNS  ̽ ִ  ڷῡ  TTL ҴѴ.

  2.6.4.  Domain Name Servers

  Ӽ authoritative Ҹ ȿ ִ ȣƮ  
    ִ.  ,  װ master name servers
  ϱ⵵ Ѵ.    ִ ȣƮ    
   ̷     ȴ.

    ȭ ϱ ؼ  װ    
  ǥ  ̴.    Ϸκ     Ű
   ߿ ϳ primary    , Ģ   
  primary   ڷḦ       ִ    ٸ secondary
     ν ̷ ۾ ̷   ִ.

   Ӽ  ߿  ϳδ  ۾ лŰ
  ؼ̰,  ٸ  δ  ۾  Ӽ
  йϱ ؼ̴. ϳ    ӽ 浹  սǰ 
    Ʈũ ῡ ߴٸ, ٸ   Ǹ û
    ̴. , ̷    ( DNS û
   ߸   س ,    α׷ 
  Ʈ װ ߻Ǵ )κ ȣ    Ѵ.

     ϰ  ִ   Ǵ  
  ε      . - ¼  ׷ 𸥴. 
  Ӽ localhost     127.0.0.1 شϴ 
   ־ Ѵ.  ׷ ұϰ ̷  ° 
  쵵 ִ. ̰   Ʈũ  ϰ ִ
  ø̼  DNS ǵ óϰ      .
    ¸ caching-only  θ.

  2.6.5.  The DNS Database

  츮  DNS ȣƮ IP ּҸ óϴ   Ӹ ƴ϶
  Ӽ  ȯϴ ϵ Ѵٴ  ˾Ҵ.  DNS
  ͺ̽  ٸ  Ʈ   .

  DNS  ̽ ִ ϳ   resource record ٿ
  RR̶ θ.   ڵ װͰ õǾ ִ ¸ 
  ְ, װ ǥϴ      , ϳ Ŭ
  װ ϴ Ʈũ ¸  ְ ִ. ڴ IP ּ 
  (the IN class) Ǵ MIT Ǵ Hesiod Ʈũ ּҿ  
  ٸ 巹    ʿ並 Ű ִ. ⺻  resource
  record ´ ϳ IP  ּҿ Բ ϳ fully qualified domain
  name õǾ ִ ϳ ڵ带 Ѵ.

  , ȣƮ  ̸   ִ.  ̷ ̸
  ϳ     Ȯε  ִ canonical host name ̾ Ѵ.
  ݸ鿡 ٸ ̸ ܼ ڿ   ϰ ִ ̴. 
  ΰ ¿   Ѵٸ, canonical ȣƮ  õǾ
  ִ ڵ尡  ϳۿ , ٸ ȣƮ canonical
  ȣƮ Ű ִ CN- AME ڵ带  ִ.

  츮 ⼭   ڵ带 ٷ  , 忡 
     ,      Ҵ. ׸ 2.4
  physics.groucho.edu (zone)    Ӽ  Ǵ 
  ͺ̽  κ ְ ִ.

          Figure 2.4: An excerpt from the named.hosts file for the Physics Department

  A CNAME ϴ ĳ,     κп  Ư
  ڵ带    . ̰ SOA (Start of Authority) ҽ
  ڵ̴. ̰    ִ Ϲ    ִ. ̸
  ׸, ̰   ڵ带  time-to-live ʱⰪ ϰ
  ִ.

   Ͽ Ʈ(.)  ʴ  ̸ groucho.edu ΰ
  Ǿ ؼ    ϶. SOA ҽ Ǵ Ư
  ̸ "@"  ü     Ÿ.

  츮  groucho.edu   Ӽ ¶  
  physics  (zone)    ˰ ְ, ׷ ׵
  Ӽ Ǹ û  ִ   ƿԴ.  ̰ 밳 ѽ
  ڵ忡  ȴ ; NS ڵ   FQDN  ְ,
  ϳ    ̸ õǾ ִ ּҸ  ִ. ̷
  ڵ尡   Բ  Ǵ ̷, װ͵  glue
  records  θ⵵ Ѵ. ̰͵   (parent zone) 
    ִ ȣƮ      ִ ڵ
  ǥ ̴. glue ڵ  ׸ 2.5  Ͱ 
  physics.groucho.edu  Ӽ Ű ִ.

            Figure 2.5: An excerpt fro the named.hosts file for GMU.

  2.6.6.  Reverse Lookups

  ȣƮ  ִ IP-ּҸ ã  ̿ܿ ּҿ شϴ ã
     ٶϴ. ̰ reverse mapping θ  ź
  ϱ 

  ؼ  Ʈũ 񽺿  ȴ. ܵ hosts  
  , reverse lookups ܼ   ǿ شϴ IP ּҸ 
  ȣƮ   ãش. DNS     ö ϰ
  ã ۾  ǿʹ  ۾̴. ſ, ݱ 
   ִ Ư   in-addr.arpa dotted-quad ǥ  
  ȣƮ  IP ּҸ  ϰ ִ.  ̸ ׸, 149.76.12.4 IP
  ּҴ 4.12.76.149.in-addr.arpa ̸ ġѴ. ̷ ̸
  װ͵ canonical ȣƮ Ų ҽ ڵ带 PTR̶
  θ.

         밳   ϴ
    IP ּҸ ȣ Ʈ Ҵϴ  ۾ ϰ   
  ִٴ  ǹѴ.  ׵ 밳     ִ ϳ̻
  IP Ʈũ   ̷, DNS (zone) IP Ʈ ũ  1
    ?  (one-to-many)  ϴ    ִ.  ̸׸,
  (Physics Department)  149.76.8.0, 149.76.12.0 ׸
  149.76.14.0 ϰ ִ.

   , in-addr.arpa ο ִ ο  physics  
    ϰ,  (department) ִ Ʈũ ڿ 
  ӹ޾ƾ Ѵ; 8.76.149.in-addr.arpa, 12.76.149.in-addr.arpa ׸,
  14.76.149.in-addr.arpa.  ׷ ʰ, Collider Lab ٰ ο
  ȣƮ ġϴ  , ׵ in-addr.arpa   (zone) Ͽ
  ԷµǾ ִ ο ּҸ  ؼ ׵ (parent) ο
   ʿ䰡  ̴.

   12   (zone) ͺ̽ ׸  2.6 Ÿ ִ.
  ׵     (parent zone)  ̽ ġϴ glue
  ڵ ׸ 2.7 Ÿ ִ.

            Figure 2.6: An excerpt from the named.rev file for subnet 12

            Figure 2.7: An excerpt from the named.rev file for network 149.76.

  ̰͵  ߿  ڸ, (zone)   IP Ʈũ
  superset     ְ, ̷ Ʈũ  ݸũ
  Ʈ  ؾ  Ѵ. Groucho  Marx п ִ  ݵ
  255.255.255.0 ݸũ , ¶ in-addr.arpa   
               ־. ׷,   ſ
  ݸũ 255.255.255.128  شٸ,  149.76.12.128 
       .  ֳϸ, 12.76.149.in-addr.arpa
        ( ȣƮ ϳ 1
  127,  ϳ 128 255 )  ִٰ DNS
    ִ   ̴.

  3.  Configuring the Networking Hardware

  3.1.  Devices, Drivers, and all that

   츮 Ʈũ ̽ Ϲ  TCP/IP  
  ̾߱    . , ϵ  κ ϴ Ŀο
  "Networking code" ü   ϴ Ȯ  Ѵ.
  ̷ 츦 ؼ,  忡 ̽    信
   ٷ  Ѵ.

  켱 ϵ  ü   ̴.  , ̴ ;
  ̰    ̷ ְ,  ӿ  ȣ  
    Ĩ ä ,  带 PC Կ Ⱦ 
  ȴ. ⼭ ̷ ġ   ̴.

  ̴ 带   ְ ϱ ؼ,  Ŀο Ư
  (ɼ)  ǥ ξ Ѵ. ׷ Ư  ġ 
  ־ Ѵ. ̷ ͵ ̸  ġ ̹ Ѵ.  ,
   ɸ鿡 ̴     ġ ̹
   ִ. ׷ ġ ̹ װ  Donald Becker
  ̸  "Becker Series Drivers" θ. ٸ  ,  D-
  Link ̹   ִ , ̰  Ʈ Ǿ ִ D-
  Link Ŷ ͸ ó ش.

  ׷, ġ ̹ "óѴ"   ǹϱ? 
  ̴ 忡     κ . ̹ ¶
  , ֺġ     ־ Ѵ : , ̹
   ɾ ͸  ϴ ݸ鿡,   ̹ 
    Ͷ ۹  ־ Ѵ.

  PC ̷   ޸   ̷, װ 
  Ϳ   ִ.  ޸𸮴 Ϲ  
  κ̳ base address  Ǿ ִ. ̴   ̽
  ּҴ 0x300, Ǵ 0x360̴.

            ׸ 3.1: ġ ̹, ̽ ׸ ϵ 

  밳,  ̽ ּҿ  ϵ  ؼ 
  ʾƵ ȴ.  ϸ, Ŀ Ʈð  ġ  
  ̴. ̷  autoprobing̶ θ. , ̰ Ŀ 
  ޸ ġ о ̰,  ̴ 尡 ġǾ ִ  
  Ϳ Ѵ. , ڵ  س   ̴  
    𸥴; ǥ   ȣȯ   ̴
  ī带   ̴. ׸  Ŀ  , ̴
  ġ   õ ̴. ,  ϳ ̻ 带
  ϰ ִٸ, ̷  Ŀο  ƾ Ѵ.

   Ŀο  ƾ ϴ  ٸ δ  ͷƮ û
  ä ִ. Ŀ ο  ϵ ǰ  ͷƮ űµ,
  ׵  ǰ  ͷƮ   ó ʿ䰡 ִ 찡  ִ.
   ,  Ͱ   , Ư ° ߻ϱ⵵ Ѵ.
  PC, ͷƮ 0 1 ׸ 3  15 ȣ ο 15
  ͷƮ äε  ϳ ߻Ѵ. ϵ ǰ  ϳ
  ͷƮȣ   ,   ̷ ͷƮȣ   interrupt
  request   number, Ǵ   IRQ. - IRQ 2 9  . ֳϸ,
  PC  8  IRQ  ͷƮ μ ٷ Ĺ迭ϰ ֱ
  ̴. ,  ° μ ù °  μ IRQ 2  
  ִ. θ.

  2忡 Ѵ, Ŀ ̸ ̽  ġ(device)
  Ѵ.  ̽   ϵ ͸ ްų
  ų ϴ ߻    Ѵ.

  ̽  ̸   Ѵ. ̷ ͵ Ŀο
  ǵȴ. , /dev 丮  ġ  ִ  ƴϴ.
    ̴ ̽  ̸δ eth0, eth1 ִ. 
  ġ شϴ ̽  Ҵ  ġ   ִ 
   ȴ; ̸׸,  ù ° ġǾ ִ ̴  
  eth0 ɰ̰,  eth1  ̸   ̴. ̷
  Ģ    ܵ ִ.  SLIP ̽  Ҵȴ.
  ٽ ؼ, SLIP  Ȯ , ̽ ø Ʈ
  Ҵȴ.

  ׸ 3.1 츮 ϵ, ġ ̹  ׸ ̽
  踦    ִ.

   , Ŀ ϴ ġ ġǾ ִ ̽ ȭ鿡
  Ÿ.    츮    ִ Ʈ ȭ̴.

       .
       .
      This processor honours the WP bit even when in supervisor mode. Good.
      Floppy drive(s): fd0 is 1.44M
      Swansea University Computer Society NET3.010
      IP Protocols: ICMP, UDP, TCP
      PPP: version 0.2.1 (4 channels) OPTIMIZE_FLAGS
      TCP compression code copyright 1989 Regents of the University of California
      dl0: D-Link DE-600 pocket adapter, Ethernet Address: 00:80:C8:71:76:95
      Checking 386/387 coupling... Ok, fpu using exception 16 error reporting.
      Linux version 1.1.11 (okir@monad) #3 Sat May 7 14:57:18 MET DST 1994

   ̰ Ŀο TCP/IP  SLIP, CSLIP ׸ PPP 밡ϰ
  ϴ   Ϻκ̴. ؿ  °   D-Link 
  Ͱ Ǿ,  ġǾ ִ ̽ dl0 
  ش.   ٸ  ̴ ī带   ٸ,
  Ŀ 밳   شϴ ī带 ؼ, eth0  
  ̽ ۽Ű     ̴.   
  ġǾ  ִ ̴ ī带  ִ ,  ޽   .
   ̰ Ŀ  带 س  ٴ  Ѵ.
  ̰Ϳ ؼ   ٷڴ.

  3.2.  Kernel Configuration

  κ    Ϲ  PC ϵ
    ִ Ʈ ũ  ִ. ̰  Ʈ ũ
  Ŀ   Ϲ  ̹   ִٴ  ǹѴ.
  ׷  Ŀ  κ  ƿ       ý
  ޸𸮸 Һϰ ȴ. ׷Ƿ,   ʿ ϰ, ϴ
   ̹ ԽѼ Ŀ ؾ Ѵ.

   ý ų ,   ڱⰡ  ִ Ŀ 
  ˰ ־ Ѵ. ̰Ϳ  ⺻ ϰ ִ δ Matt
  Welsh  " Installation and Getting Started" ִ. ̰͵ 
  Linux Documentation Project (LDP) ø ϳ ̴.  ,
  츮 Ʈŷ õǾ ִ  ɼǸ ٷ ̴.

   make config ϱ⿡ ռ, Ϲ   ؾ 
  ̴.  ׸,  Ŀ ġ μ ϰ ִ
  ƴ... ̷ ͵  ϳ ν, TCP/IP Ʈŷ ϴ
  ؾ  Ѵ.  Ʈŷ ϰ  ʹٸ 'y' Էؾ Ѵ.

  3.2.1.  Kernel Options in Linux 1.0 and Higher

  Ϲ ɼǿ  亯 ϼ Ŀ, SCSI  ̹  
     ¿   亯ؾ Ѵ.   ̴ 
  Ʈŷ   ̴.   ɼǿ   ׸ 
    ؼ  Ÿ ̸, ̷  Ŀ 
      þ ̴.  ̴   κ Ŀ 
  1.0 1.1 Ǵ ɼ̴. (׿  ּ Ÿü
  Ÿ.);

       *
       * Network device support
       *
       Network device support? (CONFIG_ETHERCARDS) [y]

   ([]) Ÿ ũ ̸  .  
   Ʈŷ  ġ , ̴, SLIP Ǵ PPP ϰ Ѵٸ,
    'y' ؾ Ѵ.    'y' ߴٸ, ڵ
  ̴  ġ ϰ ȴ. ٸ  Ʈũ ̹
  ϰ Ѵٸ,  ؾ Ѵ.

       SLIP (serial line) support? (CONFIG_SLIP) [y]
        SLIP compressed headers (SL_COMPRESSED) [y]
       PPP (point-to-point) support? (CONFIG_PPP) [y]
       PLIP (parallel port) support? (CONFIG_PLIP) [n]

  ̷  亯Ϸ   ϴ  
  ݿ ؼ    ˰ ־ Ѵ. SLIP  ø
   ؼ IP  ׷  ϴ ̴. compressed headers
  ɼ CSLIP    ε,  CSLIP  TCP/IP
    Ʈ ϴ  Ѵ.   Ŀοɼ
  ڵ CSLIP  ִ  ƴ ϶. 밳 ̰  Ư
   Ŀ  ʿ Ѵ.

  PPP ø  ؼ Ʈũ Ʈ ִ  ٸ
  ̴. SLIP  ణ ٷ , IP ѵǾ  ,
  װ  ,  IPX   . ֱٿ ͼ  PPP ɼ
   ְ ,  Ŀο   ɼ  .

  PLIP з Ʈ  ؼ IP  ׷ ִ 
  Ѵ.   밳 DOS ϰ ִ PC ϱ ؼ
  Ѵ.

     ǻ ȸ翡  ̴ 忡 
  ̴.    ̹ ߵǰ ִ.    
  ٸ 迡    ִ Ŀ  Ѵٸ, ϳ̻
  ̹   ִ.

       NE2000/NE1000 support (CONFIG_NE2000) [y]
       WD80*3 support (CONFIG_WD80x3) [n]
       SMC Ultra support (CONFIG_ULTRA) [n]
       3c501 support (CONFIG_EL1) [n]
       3c503 support (CONFIG_EL2) [n]
       3c509/3c579 support (CONFIG_EL3) [n]
       HP PCLAN support (CONFIG_HPLAN) [n]
       AT1500 and NE2100 (LANCE and PCnet-ISA) support (CONFIG_LANCE) [n]
       AT1700 support (CONFIG_AT1700) [n]
       DEPCA support (CONFIG_DEPCA) [n]
       D-Link DE600 pocket adaptor support (CONFIG_DE600) [y]
       AT-LAN-TEC/RealTek pocket adaptor support (CONFIG_ATP) [n]
       *
       * CD-ROM drivers
       *
       ...

   ý (section), , ȯ   ũƮ
  п NFS, Ʈ ŷ Ͻý    ̴.
  NFS Ͻý  ȣƮ  ִ  Ѵ.  װ
  ȣƮ پ ִ ӽ  ϵ ũ ΰó    ش.

       NFS filesystem support (CONFIG_NFS_Fs) [y]

  3.2.2.  Kernel Options in Linux 1.1.14 and Higher

   1.1.14 ణ ȯ ٲپ,  IPX 
  ߰״.   ϴ Ϲ Ʈŷ ɼ
   ̴. ̰    Ʈŷ  ǿ   Ѵ.
       *
       * Networking options
       *
       TCP/IP networking (CONFIG_TNET) [y]

   TCP/IP Ʈŷ Ѵٸ,   'y'  ؾ Ѵ.
  ׷ ʰ 'n'̶ ߴ ϴ, IPX ϴ Ŀ 
   ִ.

       IP forwarding/gatewaying (CONFIG_FORWARD) [n]

    ̴̳ ̴ݰ SLIP ũ̿  ý
  Ʈ̷ν  ϰ ִٸ,  ɼ    ִ.  ɼ
  ʱⰪ  ʴ´  ϴ , ̸ ȭ ȣƮ
  ϰ ;  𸥴. ȭ   ̻ Ʈ ũ
  Ǿ ִ ȣƮ,   Ʈũ ̿ Ʈ Ʈ 
  ʴ´.  ȭ 밳 θ δ  ִ
  ȸκ ڵ  ȣϴµ  ȴ. ڵ ȭ
  ؼ, ͳ 񽺸  ,  ȸ  
  ᵵ ȭ    , ܺ κ  ȸ
    ȣ  ִ.

       *
       * (it is saft to leave these untouched)
       *
       PC/TCP compatibility mode (CONFIG_INET_PCTCP) [n]

   ɼ  PC/TCP, DOS ʷϴ  PC, ϴ 
  TCP/IPʹ ȣȯ ۵Ѵ.     ɼ Ѵٸ,
  Ϲ ϴ UNIX    ,  迡 ϴ
  ӵ   𸥴.

       Reverse ARP (CONFIG_INET_RARP) [n]

    RARP, Reverse Address Resolution Protocol   ְ
  ش.  RARP ũ Ŭ̾Ʈ  , IP 巹
  ʿϴ X ͹̳ο  ȴ.   Ŭ̾Ʈ 
  ȹ̶,  RARP ؾ Ѵ. ֱٿ   Ʈũ Ű
  (net-0.32d) rarp ϴ  ƿƼ  ϰ ִ.  
  ƿƼ ý RARP ĳ ߰ų  ִ.

       Assume subnets are local (CONFIG_INET_SNARL) [y]

  TCP ؼ ͸  , Ͱ IP  , Ŀ
  Ŷ 帧 ߴܽѾ Ѵ. ȣƮ ؼ ̴ݰ 
   Ʈũ ؼ ͸  ,  ȣƮ հŸ
   ͳ Ŵ Ŷ      ̴.{{. ̰
  ſ  ִ Ŷũ п ϱ  ̴.  }} 
   SNARL   ʴ´ٸ, Ŀ  ׵ Ʈũ
   ϳ ̽  ִ óƮũ 
  ̴. ׷ ұϰ   Groucho Marx University ִ
  Ŭ B Ʈũ ã Ѵٸ, Ŭ B üƮũ 
  , κ ȣƮ ̽  ϳ̻  
   ̴.   SNARL Ѵٸ, Ŀ  
  ̶  ̸, п ִ ȣƮ  , Ŵ
  Ŷ ϰ  ̴.
    Ư ȣƮ  ͸ ؼ ׸ Ŷ
  ϰ  ٸ, (̸׸, SLIP  ͸  ϴ
  )  route mtu  ؼ,   ذ  ִ.
  ̰Ϳ ؼ  ǳκп ŷ  ̴.

       Disable NAGLE algorithm (normally enabled) (CONFIG_TCP_NAGLE_OFF) [n]

  Nagle ̸ tinygrams θ Ưϰ    IP Ŷ
  ϱ  Ģ̴. ȭ Ʈŷ  ̷  tinygram 
  µ, telnet  Ǵ rsh  Ʈŷ  ̷ tinygram
  . SLIP    뿪 ῡ tinygram İ  ִ.
  Nagel ˰  ȲϿ ߻ϴ ͸ TCP  
  ̴ ۾   ̴.     ۵  Ŷ Ҿ
    ִٸ, Nagle ˰    ִ.

       The IPX protocol (CONFIG_IPX) [n]

   ɼ 뺧 Ʈŷ ϴ   IPX  
  ְ  ش.  ̰  ߿ ְ,  δ  
  . ̰ ϴ Ѱ  ̶,    IPX
  ϰ  ִ DOS  ƿƼ    ְ, PPP  ؼ,
  뺧  ʸ ΰ ִ Ʈũ  Ʈ Ʈ ϴٴ
  ̴. 뺧 Ʈŷ      ״
   ,   ҺǴ      ,
  ݰ ҽ ϳ ̴.

  1.1.16 Ŀο,   ٸ  ̹   ̹
   ְ  .   ġ ̹  
   ̴.

       Dummy net driver support (CONFIG_DUMMY) [y]

   ̹ ϴ  ״  , ĵ̳
  SLIP ȣƮ  ſ ϰ   ִ. ̰ ⺻
   ̽ ŽĿ̵  ̴.  ̽
  ϴ  ̴ݿ ƴ SLIP ϴ ȣ Ʈ ϱ
  ̸, ̰ ׻  IP 巹 Űµ  
  .  ̽   ڼ  5忡 ٷ̴.

  3.3.  A Tour of Linux Network Devices

   Ŀ   ؼ  ϵ ̹
   ش.       ִ ̹ װͿ شϴ
  ̽   ϰڴ.

   ǥ ϴ ̽ ִ. ϳ̻
  ̽  ϴ κ ̹  ̽ ̸  eth0,
  eth1   ȣ ο  ִ.

     lo   ̽. Ʈũ ø̼ Ӹƴ϶ 
         ȴ.   ,  ͱ׷ 
        ȣƮ Ʈŷ ǵ  쿡 ġ ȸο
         ۵Ѵ. Ŀο ׻  ϳ ̻  ġ
        Ÿ ִ.

     ethn
        n° ̴ ī. κ ̴ 忡  ϴ Ϲ
        ̽ ̸.

     dln
         ̽ D-Link DE-600  Ϳ,  ٸ ̴
        ġ  .  ̰ з Ʈ  ϴ
        DE-600 Ưϰ ȴ.

     sln
        n° SLIP ̽. SLIP ̽ SLIP Ҵϴ ø
          Ѽ    ִ. , SLIP ϰ
        ִ ù ° ø  sl0 ȴ. Ŀ ְ   SLIP
        ̽  ش.

     plipn
        n° PLIP ̽. PLIP з  ؼ IP 
        ׷  .  Ŀο ְ   PLIP ̽
          ְ ִ.  ̽ ý  , PLIP
        ̹  ҴǸ, з Ʈ ȴ.

  ISDN Ǵ AX.25  ̽ ̹ ̷ ߰
  𸥴. IPX (  Ʈŷ ) AX.25 (ham radio amateurs
  )  ̹   ߿   ʱ ܰ迡
  ӹ ִ.

    츮   ̹ 뿡  ڼ 
  ٷ ̴.

  3.4.  Ethernet Installation

    Ʈũ ڵ    ̴ ī ǥ   ְ
  ִ. κ ̹ Donald Becker
  (becker@cesdis.gsfc.nasa.gov)     ִ.   National
  Semiconductor 8390 chip ϴ ī带  ̹ 
   .  ̹ Becker Series Drivers 츮  ˷
  ִ.  ̹ ߿ з Ʈ ؼ ̴ݿ   ְ
  ִ D-Link  ͸    ִ. ̷ ̹
  Bj rn Ekwall (bj0rn@blox.se)   . DEPCA ̹
  David C. Davies (davies@wanton.lkg.dec.com)   .

  3.4.1.  Ethernet Cabling

    ϻ  ѹ ̴ ġϰ Ѵٸ,  
  ̶̺   п  ̴. ̴ ̺
  ؼ ſ ٷӴ.  ̺    ʹ 50 (ohm)
  ߾ ־ ϸ,   ؼ  װ͵  
   ȵȴ. (̸׸,   ̺ Ÿ(star-shape)
  Ǿ  .   T · յǾ ִ BNC ĿͿ
  Բ   ̺  ϰ ִٸ, ݵ  ĿͿ
   κ Ƽ Ѿ Ѵ.

    thicknet Ϸ Ѵٸ, ݵ Ʈù
  ļ  ȣ Ʈ ˽Ѿ Ѵ. ( ̰ Ethernet
  Attachment Unit  θ.)   Ʈù 忡 ִ
  15 AUI Ʈ ȾƳְ ǵ ̺   ִ.

  3.4.2.  Supported Boards

  ϰ ִ   Ʈ  Ethernet HOWTO 
  ϶. ̰ Ŵ Paul Gortmaker. - Paul   ִٸ,
  gpg109@rsphysse.anu.edu.au ϱ ٶ.  
  comp.os.linux.announce Ʈǰ ִ.

  ⿡  ϵ  ϴ  θ  ˷ 带
  ְ ִ.   HOWTO Ͽ ⼭    
     ִ.   Ͽ   ִ ̴ 带
  ã Ѵٸ, HOWTO    .    
  ̷ ī带  ϴ ߿ ׸ ϴ  쵵 ִ.
  DMA ʸ ΰ ִ ̴  Adaptec 1542 SCSI controller
   DMA ä  Ѵ.  ̴  DMA ä ٸ
   ٲپ  ʴ,  ̴  尡  Ŷ Ͱ
  ġϴ   Ҽ ִ.

     3Com EtherLink
        3c503, 3c503/16, 3c507 ׸  3c509 Ѵ. 3c501
          ̰ ӵ ſ .

     Novell Eagle  NE1000  NE2000 ׸   ȣȯ.
        NE1500 NE2100 Ѵ.

     Western Digital
        SMC/WD8003 WD8013 (SMC Elite  SMC Elite   Plus .)  
        ϸ, SMC Elite 16 Ultra Ӱ ϰ ִ.

     Hewlett Packard
        HP 27252, HP 27247B, ׸ HP J2405A Ѵ.

     D-Link
        DE-600  , DE-100, DE-200 ׸ DE-220-T Ѵ.
        ׸, PCMCIA ī. - ٸ ž Ǿ tsx-11.mit.edu
        ִ packages/laptops ö ִ. DE-650-T  ġ
        Ŷ ִ.

     DEC
        DE200 (32K/64K), DE202, DE100 ׸ DEPCA rev E Ѵ.

     Allied Teliesis
        AT1500 AT1700 Ѵ.

   ̷ ī  ϳ ϰ Ѵٸ,   
  ԵǾ ִ Ŀ Ͽ   ִ. ̷ ī
  Ϲ ׿ شϴ ̹  ִ. Ⱓ 
  ϰ  Ѵٸ,   ʿ ̹  Ŀο
  ԽѼ  ϴ   .

  3.4.3.  Ethernet Autoprobing

   , ̴ ڵ  带    
  ̴.   ڵ  ̴ 巹  ī带 ˻
  ̴.

  κ ڵ忡 ΰ Ѱ谡 ִ.   ϳ  带
   ν  ٴ ̴. ̰ Ϲ  ȣȯ
  WD80x3 忡  ߻ϴ  ̴.  °  Ŀ 
  ϳ ̻ 带 κ  . ̷     
  尡  ̽  ϴ 𸣴 Ͱ    
  ִ.

    ϳ̻ 带 ϰ ְų, κ갡 
  带  ϴµ ߴٸ,  ݵ ī ̽
  巹 ̸ Ŀο ؾ Ѵ.

  Net-3, ̰ ϱ ؼ ΰ ٸ     
  ִ.   Ѱ δ Ŀ ҽ ڵ忡 ִ
  drivers/net/Space.c  (̹      ִ.)
  Ư  Űų ߰ ִ ̴.  Ʈ ŷ
  ڵ忡 ͼ ִٸ   õ  ְ ʹ.   δ
   ,    Ŀο ϴ ̴.   Ʈ ý
  lilo Ѵٸ,  lilo.conf Ͽ append ɼ  ν
  Ŀο ִ   ׳ ĥ  ִ. ̴ ġ   
  Ŀο ϱ ؼ,  ̴    ִ.

       ether=irq, base_addr, param1, param2, name

  ó    ڷ Ǿ  ִ ݸ鿡   ġ
  ϴ   .  ڰ Ƿ ߰ų  ִ; 
  װ͵ ϰų 0   ٸ, Ŀ  ġ
  ˻ν,   س ϰų ʱⰪ    .

  ù °  ġ ҴǾ ִ IRQ ϴ κ̴.
  ʱⰪ, Ŀ  ġ IRQ ä ڵ   ̴. 3c503
  ̹ Ư  ¸  ִ.  ̰ IRQ 5, 9, 3, 4
  ϰ,  ο ϱ  带 Ѵ.

  base_addr  忡 I/O ̽ 巹 ִ   Ѵ;
   ô  巹 ˻ϱ ؼ Ŀο 0̶  ־
  Ѵ.

      ٸ  ̹ ٸ  
  ִ. WD80x3    ޸ 带 ϱ ؼ,  ޸
   ۰  巹  ־ Ѵ. ٸ ī 밳
     ϱ ؼ param1   Ѵ. 1 7
  ڴ     ϴ  Ÿ. ݸ鿡  8 
   ٸ   Ѵ; 0 ʱⰪ ǹѴ.  3c503 ̹
   Ʈù (ʱⰪ) Ǵ ܺ Ʈù (ڰ 1)  ϱ
  ؼ param2 Ѵ.   忡 پִ BNC Ŀ͸
  ϰ, ڴ AUI Ʈ Ѵ.

      ̴ 带  ִٸ,  ڵ
  ִ ϳ 带   , lilo   °  
  ĥ  ִ.  ׷   ̹   ° 带
  ã Ȯؾ Ѵ. ׷ ,  ٸ     ϵ
  ʴ  ߻   ִ.  lilo ִ reserve ɼ
  ׳ ġ ν ̷  ذ  ִ.  ° 忡
  ־ I/O   ϱ ؼ Ŀο и  ξ
  Ѵ.

  ̸׸,  ̽ eth1̰ 巹 0x300  ִ ̴
  带   ġϰ Ѵٸ,  Ŀο ִ  
   ־ Ѵ.

       reserve=0x300,32 ether=0,0x300,eth1

  reserve ɼ  ġ ˻ ,  I/O   ϴ
  ġ  ȮѴ.   eth0 κϴ ۾
    ؼ Ŀ     ִ.

       reserve=0x340,32 ether=0,0x340,eth0

   κ ϱ ؼ,    base_addr
      .

       ether=0, -1, eth0

  3.5.  The PLIP Driver

  PLIP, Parallel Line IP    ǻ   ؼ
  Ʈũ ϰ   ϴ   ̴. ̰ з
  Ʈ 10kBps 20kBps ӵ   ִ Ư ̺
  Ѵ.

  PLIP  ֽȸ Crynwr  ̴. ̰  з Ʈ
  Ͽ PC  ð Ʈũ ϱ  ,  
   Ʈ Ѵ;   PC ֺġ ͸  
       θ    . PLIP Է ؼ
  Ʈ ټ  θ ν ̷ ۾   Ѵ.
  ׸ PLIP  ͸ 4Ʈ ؾϴ    
  ִ.    带 mode zero PLIP θ. ó, ̷ 
   Ʈ  ̻    ʰ ִ. ׷, mode 1̶ θ
  PLIP ȮŲ   Դµ, ̰  ü 8Ʈ ̽
  ϰԲ ۵Ǿ.

  ,   mode 0   ְ ִ. ̰  PLIP ʱ
  ڵʹ    ϰ  ٸ.    Crynwr  ϴ
  PLIP  NCSA   telnet. - NCSA telnet ̴ Ǵ PLIP  DOS
  TCPIP ִ Ư α׷̸, telnet FTP  ְ
  ִ./ ϴ PLIP ̹ ȣȯ   ִ
  ߼̴. PLIP ؼ   ǻ͸ ϱ ؼ,  
  Կ  Ǹϰ ִ  "Null Printer" Ǵ  "Turbo Laplink" ̺
   Ư ̺ ؾ Ѵ.   ڽŵ  ̰
    ִ.  ̰Ϳ  ڼ  η A Ұϰ ִ.

   ϴ PLIP ̹    ̷
  ̴. ̰  Niibe Yutaka ϰ ִ.   ̹
  ߰Ǿ ִ Ŀ ϵǾ ִٸ,   Ʈ  Ʈũ
  ̽ Ǿ  ̴. plip0 з  Ʈ lp0
  ġϸ, plip1 lp1 ġѴ. Ʈ ̽ ϴ  ۾
    ;

    ٸ    Ʈ ϰ ִٸ, 
  Ŀ ҽ Ǵ ο Ŀο ִ drivers/net/Space.c ִ 
   ־ Ѵ.

   ̷ ۾   ϴ з Ʈ 
   ִٴ  ̴ ƴϴ. ġϴ ̽ Ǿ PLIP
  ̹   ִ.

  3.6.  The SLIP and PPP Drivers

  SLIP (Serial Line IP) PPP (Point-to-Point Protocol)  ø 
    IP Ŷ  ݷ θ ˷ ִ. 
  ͳݿ  ǻ͸ ٽŰ  SLIP  PPP
   ְ ִ. ׷  ڿ IP   ְ ִ.

  SLIP PPP ϱ ؼ, ϵ   ʿ  ;
    ø Ʈ   ִ. ø Ʈ ȯ  TCP/IP
  Ʈŷ õǾ      忡 ̰Ϳ  
   ִ.  ڼ   ʹٸ,  4  ϱٶ.

  4.  Setting up the Serial Hardware

  netland    T1 ͳ ũ  Һ ʰ,
  ڽ PC  ´ٴ Ӱ ִ. ׷  ұϰ, 
     ޱ ؼ,  SLIP ũ, UUCP Ʈũ,  ȭ
  ϴ ڰԽ ýۿ Ѵٰ ϰ ִ.

   忡 ׷  ϱ  𵩿 ϴ 
  鿡 ʿ     ̴.  忡 ׷
       ִ  ƴ . ̸׸,  
  ̾  ϴ   ͵... ̷  ȭ Greg
  Hankings. -  ּҴ gregh@cc.gatech.edu̴.   Serial HOWTO
  ϵǾ  ̸,  comp.os.linux.announce õȴ.

  4.1.  Communication Software for Modem Links

   ϰ    ִ   Ű ִ. ̰͵
  κ terminal program̶ ϴ ε, ̰ ڰ ٸ
  ǻͿ ϴ   ش. Ϲ ϴ ͹̳
  α׷δ kermit ִ. ȭȣο  ǻ  ýۿ
  ϰų ȭ ɾִ ũƮ  ִ  ǰ,
    α׷ 󸶵 ִ. װ͵ ߿ ϳ minicom̶
   ִµ, ̰   ִ ڵ ͹̳ α׷
    ְ ش. ̷  α׷  seyon̶ ϴ
  X  Ű ִ.

   BBS Ű  ڰԽ Ϸ  鿡
   ְ ִ. ̷ Ű  Ϻδ sunsite.unc.eduƮ
  /pub/Linux/system/Network  丮 ã  ִ.

  ͹̳ α׷ ٸ  ǻͿ ٸ  ͸
  ϱ   ȭ ø ũ ϴ Ʈ  ִ. 
   ؼ   ̶,   ųιƮ ũ ͸
  ۹ , ̸׸, Ϲڽ ִ ¶    ,
  Խǿ ִ    ð    ִٴ ̴.
    ,  ޴   ʱ   
  ũ  ʿ  Ѵ.

  ̷    Ʈ Ѵٸ, װ ٷ  UUCP
  ̴.    ȣƮ  ȣƮ   ,
   ȣƮ α׷  Ű  ,  α׷̴.
  ̰ 밳  Ʈũ      Ѵ.
     ִ Ian Taylor UUCP Ű   
  ϰڴ.  ȭ   Ʈ Fidonet    ȴ.
  ifmail   Fidonet ø̼ Ʈ ϰ   ִ.

  SLIP, serial line Internet protocol ȭ (interactive) ȭ
  α׷̿  ߰ Ű  Ѵ.   ׵ и
  ̾ϰų FTP   ϱ  Ϲ ϴ  SLIP
    SLIP Ѵ. SLIP   γ ݿ
   LAN-to-LAN Ŀø  ϱ⵵ ϸ, ISDN 
  Ѵ.

  4.2.  Introduction to Serial Devices

  ø ġ ϱ  Ǵ  н Ŀ ġ tty,
  TeletypeTM̶  θ . ̰ ʱ н  ͹̳ 
  ü ѱ ߴ.  ڷ  ͸ óϴ ͹̳
  · ϰ ִ.    ؼ, 츮 Ŀ ġ   
    ̴.

       tty: () ܼ,
  pseudo(ǻ)-͹̳ (X11  ø̼ ϴ two-way
   ϴ.) ׸ ø ġ Ѵ.   ͵
  ø  ؼ ȭ  ϱ   ̰͵ tty
  Խ Ų: ̰ ͹̳   ϵ ̾ ͹̳̳
  Ʈ ǻͿ   ̴.

  Tty    , ̰ ioctl(2)  ý 
  ϵ Ǿ ִ. ̰͵  ټ tty   
   óϱ   ϰ   ʿ䰡  ķ, 
  ø ġ ߾ ִ.

   Ư     ӵ иƼ   ִ.
  ׸, 빮ڿ  ڸ ȯִ ɼǰ ๮ (line feed)
  ٲپִ ɼǵ ִ.  tty  ̹ line discipline 
  ִµ,  ̰  ٸ ϴ  ġ ̹  
  Ѵ.  ,  ϴ SLIP ̹ line
  discipline  ϱ⵵ Ѵ.
   ӵ   ϴ Ʈ ִ. ùٸ  Bit
  rate ϴµ,     ӵ ǹϸ, ʴ  ۵Ǵ
  Ʈ (bps) ϴ ̴. ,  鿡 Baud
  rate ϴ   ̴. ̰ ״ ùٸ   
  ƴϴ. ̷ ΰ    ٲپ   . Baud
  rate   ø ġ  Ư ϴ ̸, ַ
  ۵Ǵ ޽ Ŭ   ̴. Bit rate  
  ϴ ø    ¸ ǹϴ ̸, ַ ʴ
  ۵Ǵ  Ʈ   Ų.  ޽ ߻   Ǵ
  ϳ ̻ Ʈ ڵ Ű κ ġ  ΰ 
  ٸ ȴٴ   ƴ  ſ ߿ϴ.

  4.3.  Accessing Serial Devices

  н ϴ  ġ  ϰ, ø  Ư
  ġ  ؼ   ִ.  ġ  /dev  丮
  ġ ִ.  ġϵ ø ̹  Ʈ Ǿ ִ
  ġ ΰ    ִ. ̷ Ͽ ϰ ִ
  ġ  ٸ  ̴.

  ù ° ġ Ʈ ؼ ̾   Ѵ; 
   ֹȣ ϸ,  ̸ ttyS0, ttyS1 ִ.   ° ġ
   Ʈ ؼ ̾     Ǹ,  ̸
  cua0, cua1 Ѵ. ټ  ֹȣ Ѵ.

    COM1 COM4 Ʈ ϳ Ѵٸ,  ȣ COM
  Ʈȣ  63    ̴.  ̿ ٸ 
  Ұų,  ø   ϴ 带 ϰ ִٸ, Serial
  HOWTO о ٶ.

    COM2 ߾ Ҵٰ  . ιȣ 65
  ɰ̸, ֹȣ  ̾ ƿ  5  ̸, ġδ
  cua1 ؾ Ѵ. /dev   ø tty ִ. ټ
  °  °  ĭ   ȣ  ȣ  ִ ̴.

       $ ls -l /dev/cua*
       crw-rw-rw-   1 root        5,   64 Nov 30 19:31 /dev/cua0
       crw-rw-rw-   1 root        5,   65 Nov 30 22:08 /dev/cua1
       crw-rw-rw-   1 root        5,   66 Oct 28 11:56 /dev/cua2
       crw-rw-rw-   1 root        5,   67 Mar 19  1992 /dev/cua3

  ̷ ͵ ƹ͵ ٸ, Ʈ ؼ, ̷  
  ־ Ѵ

       # mknod -m 666 /dev/cua1 c 5 65
       # chown root.root /dev/cua1

    ڵ  ġ Ʈ cua1̶  
  ʾƵ   /dev/modem ɺ ũ ⸦ ϱ⵵  Ѵ.
  ׷  α׷  modem̶ ġ   , 
  ġ ؾ  ϴ 쵵 ִ. ̷  α׷  ġ
  ϴ ȣ ̸ lock files  ϱ ̴.  ʿ
  , cua1 ϴ   LCK...cua1 ȴ.  Ʈ
   ٸ  ġ  Ѵٴ  α׷  ٸ  lock
  file ν ϰ  , ÿ ġ ϵ  Ѵٴ
  ǹ̴.   , ø̼ǵ  ۵ 
  ̴.

  4.4.  Serial Hardware

    RS-232 ǥ ϴ   ø 带
    ְ  . RS-232  PC 忡 Ǵ  ø
   ǥ ԰̴. ̰ ܵ Ʈ  Ӹƴ϶ Ʈ ⸦
    ȸε  Ѵ. ߰ Ǵ ε  𵩿
  ϴ ݼĿ handshake   Ÿֱ  ̴.

   ϵ handshake Ƿ  ϴ , ſ ϰ
  δ. ̰ ͸  غ Ǿ ִ Ÿ ִ ¿
  ڰ  ͸ ó Ҷ  ߾  ־ ϴ
  ° ִ.  ̷ ¸   "Clear  to Send" (CTS)  "Ready to
  Send" (RTS) θ, Ϲ ϵ handshake ν, ַ
  "RTS/CTS" θ.

  PC, RS-232 ̽ 밳 National Semiconductor 16450 Ĩ Ǵ
  ̰    NSC 16550A. - NSC 16550̶ ͵ ,
  ̰ FIFO   ۵  ʴ´.  UART Ĩ Ѵ.
   ǰ (Rockwell Ĩ ϴ κ  ) 
  ٸ Ĩ ϰ ,  Ĩ ġ 16550  ó ۵ϵ
  α׷Ǿ ִ.

  16450Ĩ 16550Ĩ ֿ ̶ Ѵٸ, ڴ 16 Ʈ FIFO
  ۸  ִ ݸ, ڴ  1  Ʈ ۸  ִٴ
  ̴.  16450Ĩ ְ  ӵ 9600 忡 ϰ  ִ
  ݸ, 16550 ȣȯ Ĩ  ̻ ӵ ʿ Ѵ.   
  UART Ĩ̿  8250 Ĩ Ѵ.

  Ŀ ⺻ ȯ漳  , COM1 COM4    ǥ ø
  Ʈ Ȯ Ѵ.  ߵ  Ʈ ιȣ 64 67
  ġ Ҵ ̴.

   ø Ʈ  ϰ Ϸ  Ѵٸ, rc.serial
  ũƮ Ted Tso setserial  ġؾ Ѵ. ý ýÿ
    ũƮ /etc/rc ȣ ̴.   rc.serial ũƮ
   :

       # /etc/rc.serial - serial line configuration script.
       #
       # Do wild interrupt detection
       /sbin/setserial -W /dev/cua*

       # Configure serial devices
       /sbin/setserial /dev/cua0 auto_irq skip_test autoconfig
       /sbin/setserial /dev/cua1 auto_irq skip_test autoconfig
       /sbin/setserial /dev/cua2 auto_irq skip_test autoconfig
       /sbin/setserial /dev/cua3 auto_irq skip_test autoconfig

       # Display serial device configuration
       /sbin/netserial -bg /dev/cua*

      ˰ ʹٸ, setserial Բ  
  о ٶ.

    ø ī尡  ʾҰų,  setserial -bg ɾ
  ߸   ȭ鿡 Ѵٸ,    ȯ 
  ־ Ѵ. Rockwell() Ĩ   ִ   ϴ
  ڵ     ־.   UART Ĩ NSC
  16450 Ǿٸ,  װ NSC 16550 ȣȯĨ̴. ⼭
       ٲپ ־ Ѵ.

       /sbin/setserial /dev/cua1 auto_irq skip_test autoconfig uart 16550

  COM Ʈ, ̽ 巹 ׸ IRQ  ϴ ɼǵ ̿
  ϴ. ̰  ؼ setserial(8) Ŵ  ϱ
  ٶ.

    ϵ ڵũ ϰ ִٸ,  װ
  밡 Ȯ ؾ Ѵ. κ  α׷ ̰
  밡ϰ   ʴ´.       ־
  Ѵ.  stty  ϸ, rc.serial ũƮ    ȴ:

       $ stty srtscts < /dev/cua1

  ϵ ڵũ ȿ ˻ϱ ؼ   
  ־.

       $ stty -a < /dev/dua1

  ̰ п ġ   ɼ  ̴; ɼǾտ 
  '-' ٿ ش.   -crtsctsɼ װ ִٴ 
  ǹѴ.

  5.  Configuring TCP/IP Networking

   忡  ǻͿ TCP/IP Ʈŷ  ʿ 
  ׵  ٷ  ̴. IP ּ Ҵ  ؼ, õõ
  TCP/IP Ʈŷ ̽ ȯ汸  س ̴. ׸
    Ʈũ ġ   ߻ϴ     ذϱ
   ϰ   ִ   Ұ ̴.

   忡 ϴ κ ۾ Ϲ ѹ ؾ  ۾̴.
   Ʈ ũ ο ý ߰Űų ý ü
  籸 , κ ϵ  ־ Ѵ. TCP/IP ϱ
   ϴ   ɵ ý õǴ ð  ȴ.
  ý ý Ǵ ϵ /etc/rc ũƮ ҷ´.

   ũƮ Ʈũ  Ǿ ִ     
  rc.net Ǵ rc.inet Ѵ. ,  rc.inet1 
  rc.inet2 ϴ   ũƮ     ̴. ڰ
  Ŀ Ʈŷ κ ʱȭ Ű ݸ, ڴ ⺻ Ʈŷ
  񽺿 ø̼ Ű  Ѵ.   ʹ ڿ
   븸 ٷ ̴.

   忡 rc.inet1 ũƮ ϴ ۾  ٷ ̰, 
  (6)  װͰ Ǿ ִ ø̼ǿ  ٷ ̴.
       о   ,  ǻͿ TCP/IP
  Ʈŷ ϰ    ̴.  ׷ , rc.inet1 ִ
     ؼ ũƮ ϶. ׸  , õ ð
  rc.inet1 Ǵ Ȯϰ ǻ͸ ϶.  ϴ
      rc ũƮ õǾ ִ    
  ̴.

  5.1.  Setting up the proc Filesystem

  Net-2     proc Ͻýۿ ϰ  ִ.
  ̰ Ͻý۰  ī ؼ Ŀη run-time 
  ϰ  ϴ ̴̽. Ʈ Ǹ,  ٸ
  Ͻýۿ   ϰų     ִ. ý 
   緮 Ÿ loadavg ϰ meminfo ϰ ִ
  ׸  core ޸𸮿   Ÿ ش.

  ⿡ Ǵ Ʈŷ ڵ net 丮 ߰Ѵ. 
  丮 Ŀ ARP ̺, TCP/IP  , ׸  ̺
      Ѵ. κ  Ʈũ   ̵
  Ϸκ ׿ õǾ ִ  ´.

  proc  ý (Ǵ procfs ε ˷ ִ.) 밳 ýð
  /proc Ʈ .    /etc/fstab   
  ߰ ִ ̴.

       # procfs mont point:
       none /proc proc defaults

  ׸, /etc/rc ũƮ "mount /proc" Ų.

   ͼ procfs κ Ŀο ⺻ Ǿ ִ.
   procfs   Ŀο  ʴٸ,  "mount:  fs  type
  procfs not supported by kernel"   ޽  ̴. ̷
    Ŀ  ϰ   procfs   θ 
  , 'y' ؾ Ѵ.

  5.2.  Installing the Binaries

     Űȭ   ϰ ִٸ,
  װ Ƹ Ʈ ŷ ø̼ǰ ƿƼ  
   ̴. ׷ 쿡,    ο Ŀ 
  ġϰ  , ο ƿƼ ϴ ٽ ġ  ־
  Ѵ. ο Ŀ   Ŀ Ʈŷ   
  ϴ   ִ. ̷ 쿡  ⺻  
  ־ Ѵ. ¼, Ŀ   ϴ 쿡 ֽ
  ̳ʸ Ű ʿ 쵵  ִ. ̰͵ 밳 Ŀΰ Բ net-
  XXX.tar.gz ̸ Ǿ ȴ.  XXX  ȣ̴. 
    1.0  ´  0.32b̸, 1.1.12  Ŀ 0.32d
  ʿ Ѵ.

    ǥ TCP/IP  Ʈũ ø̼ ġϰ
  ϰ Ѵٸ,  κ  FTP Ʈ Ŀ
  ҽ    ִ. Net-BSD Ǵ   ҽ ټ ϰ ġ
  ͵ ִ. Xmosaic,  xarchie Ǵ Gopher IRC Ŭ ̾Ʈ 
  ø̼ǵ  ؾ Ѵ.

  Net-3  FTP Ʈ sunsite.unc.edu <http://sunsite.unc.edu>
  ̸,  Ʒ system/Network/sunacm ̷Ǿ ִ sunacm.swan.ac.uk
  <http://sunacm.swan.ac.uk> ִ.  ֽ Net-2e ġ Ŷ ̳ʸ
  ftp.aris.com <ftp://ftp.aris.com>  ã   ִ. BSD Ļ
  Matthias Urlichs Ʈŷ  ڵ ftp.ira.uka.de
  <ftp://ftp.ira.uka.de> ִ /pub/system/linux/netbsd  
   ̴.

  5.3.  Another Example

   å  κп Groucho Marx University   ܼ
     ڴ. ׸   εġԵ  ۾ ݴ
    ϰڴ.  virtual beer ϴ Virtual Brewery
  ϴ ׸ ȸ簡 ִٰ . ׵    ȿ
  ϱ ؼ, virtual ڰ ׵ ǻ͸ Ʈũ 
  Ϸ Ѵ. ׸ Ʈũ ϰ ϴ ǻʹ  1.0
  Ű Ѵ.

   ǹ ǳ ׿   ϴ Virtual  Winery ִ.
  ⼭ ׵ ü ̴  ִ.  ȸ 濵
   ׵鸸 Ʈũ   Ѵ. ù ܰν,  
  ̿ ͸ ϱ  Ʈ ȣƮ  ǻ͸ 
  ̰, ϰ  ȯϱ , UUCP ٱ   ũŰ 
  ̴. ׸  ͳݰ  ؼ SLIP  Ϸ 
  ̴.

  5.4.  Setting the Hostname

   δ ׷ٰ   , κ Ʈũ ø̼
   Ʈũ ϰ , ġ ´   Ǿ ִ.
  ̰ 밳    hostname  Ŵν ȴ.
  hostname ̸ ϱ ؼ   ؾ Ѵ.

       # hostname name

  ̰ ؼ γӾ ȣƮ (unqualified  hostname)
  ϴ   ̴. ̸׸, Virtual Brewery ִ ȣƮ
  vale.vbrew.com Ǵ vlager.vbrew.com   ִ. ̰͵
    ϴ ̸̸, fully qualified domain name
  (FQDN)̴. ׵  ȣƮ vale   ù ° ̸ 
  ̴.    ȣƮ ȣƮ IP ּҸ ãƳ µ
   Ǳ ,   resolver library ȣƮ IP ּҸ
  ãƳ  ִ Ȯؾ Ѵ. , ̰  /etc/hosts  
  ̸ Է ־ ȴ  ǹ̴.

    FQDN  κп   ϱ ؼ,
  domainname  ɾ  ϶ ϱ⵵ Ѵ.  
   hostname domainname   ؼ, ٽ
  FQDN   ִ.  ̰ ְ  ƴϴ. ȣƮ NIS
   ϱ ؼ Ϲ domainname  Ѵ. 
     ִ ΰ  ٸ. NIS 10忡 
   ϰڴ.

  5.5.  Assigning IP Addresses

   ȣƮ standalone operation (̸׸, INN ݴ
  Ʈ    ־ Ѵ.)  Ʈŷ Ʈ
  Ѵٸ,   ʾƵ ȴ. ֳ , п ʿ 
    ̽ (׻ 127.0.0.1̴.)  IP  ּҸ ʿ
  ϱ ̴.

  ̴ݰ   Ʈũ   ۾  ʿ Ѵ.
   ȣƮ   ϰ ִ Ʈũ ϱ ϰ
  Ѵٸ, ϰ ϴ Ʈũ IP ּҸ   ִ
  ڿ  ƾ Ѵ.     Ʈũ
  Ѵٸ,     ڽſ IP ּҸ Ҵ ־
  Ѵ.

   Ʈũ ִ ȣƮ 밳    IP Ʈũ
  ּҸ  ؾ Ѵ.   IP Ʈũ ּҸ Ҵ ־
  Ѵ.        Ʈũ  ִٸ,
  ٸ  Ʈũ ȣ װ͵鿡 Ҵ ְų,  ϳ IP ּҸ 
  Ʈũ ɰ  Ʈŷ ؾ Ѵ.  Ʈ
  ũ ͳݿ Ǿ  ʴٸ, Ʈũ ּҸ  
   ִ.    Ŭ A, B Ǵ  C  ϳ  ʾҴٸ,
   Ʈũ Ȯϰ ۵  ̴. ,  
  ̷, ͳ  ̶,  IP ּҸ ؾ Ѵ. 
  ּ   Ʈũ  ι̴  
  .  ͳݿ  쿡 Ʈũ ȣ ϰ 
  , hostmaster@internic.netκ Network Address Application
  Form ؾ Ѵ.

    ̴ ϱ ؼ  Ʈũ 
  ƾ   .    ϳ ̻ broadcast
  network    ʿ ٴ  ˾ ξ;  ⼭
  point-to-point ũ   ʴ´.  ,   ̴
   ְ, ϳ ̻ SLIP ٱ Ű Ѵٸ,
   Ʈũ    ʾƵ ȴ.  
  7忡 ϱ ϰڴ.

  Ѱ ,  Ʈũ ڰ Ŭ B شϴ Ʈũ
  ȣ NIC  ûϰ  192.72.0.0  ο޾Ҵ.  
  ̴ ϱ ؼ,  ڴ ߰  Ʈ ִ
  ȣƮ κп شϴ 8 Ʈ ϱ Ѵ.   Ǹ, 
  ݿ 254 ȣƮ ο   ִ 8 Ʈ  ٽ 
  ȴ.  ׸ , ڴ  ȣ  brewery 1,
  winery 2  ȣ Ҵ . ׷,  Ʈũ ּҴ
  191.72.1.0 191.72.2.0 Ǹ,  ũ 255.255.255.0 
  ̴.

    Ʈũ Ʈ  ϰ ִ  vlager װ͵ 
  1̶ ȣ Ʈ ȣ Ҵ޾, IP  ּҷδ  191.72.1.1
  191.72.2.1  ־. ׸ 5.1   ݰ Ʈ̸
  ش.

         Figure 5.1: Virtual Brewery and Virtual Winery - the two subnets.

      ̰ ϱ  Ŭ B Ʈũ
  ϰ ִ; Ŭ  C Ʈũ ݴ ̴. ο Ʈŷ
  ڵ带  ִ   Ʈ ٿ ѵǾ  ʴ.
  ׷,   Ŭ C Ʈũ    ⵵
  Ѵ. ̸׸,  ݸũ ȣƮ κп شϴ 2Ʈ
     ִ. ׷ Ǹ,    ݿ 64 ȣƮ
  ο  ְ ȴ.  -    ڴ εĳƮ ּҷ
  Ǿ ִ. ׷ ǻ  ݸ 63 ȣƮ ο 
  ִ.

  5.6.  Writing hosts and networks Files

   Ʈũ  , /etc/hosts  ϱ
  ؼ  ȣƮ  ַ(hostname resolution) غؾ
  Ѵ.  DNS address resolution   NIS  
  ƴ϶, hosts Ͽ  ȣƮ ־ ξ Ѵ.

    ۵Ͽ DNS NIS ϰ ϴ 쿡,
  /etc/hosts ִ  ȣƮ   ; 
  𸥴. Ѱ  ,  ýÿ ƹ Ʈũ ̽
  ǰ   ʴ ϴ,  name resolution  ;
   ̴. ̰ ſ    Ӹƴ϶, rc.inet ũƮ
  ¡ȭ ȣƮ ϵ  ش.  ׷, IP ּҵ
  ϰ   , Ŵ rc   ϴ , ŵ
  hosts  ǻͿ  ϰ ,  ؾ Ѵ. 밳,
   hosts   ȣƮӰ ּҸ ־  ̴. ׸ 
   Ѵٸ, Ʈ̿ NIC  ߰Ѿ Ѵ.  - 
   Peter Eriksson NYS Ѵٸ,  NIS  ּҰ
  ʿ   ̴. ypbind  ٸ NIS ۾ ð ׵
   ġѴ.

  ʱȭ ׽Ʈȿ,  resolver  hosts Ͽ 
  ϴ Ȯ ؾ Ѵ.  DNS Ǵ NIS Ʈ װ͵
  Ǿ ,  ̻  ʷϴ ϰ  𸥴.
  ȣƮ IP ּҸ  ã ,  /etc/hosts  ϴ 
  ø̼  ؼ,   /etc/host.conf 
   ־ Ѵ. Ʈ     ߰϶.

       order hosts

  resolver ̺귯  6忡 ϰ ٷ ̴.

  hosts   ο IP ּ, ȣƮ, ׸ ߰ 
  ȣƮ     ִ.  ʵ ̳ 
  , ּ ʵ ù ° ĭ   ؾ Ѵ. ù ° ĭ
  ؽǥ (#)  ִ  ࿡ ּ óȴ.

  ȣƮ FQDN̳     ִ. vale  
  .   밳 vale.vbrew.com  ϰ ڰ 
  ̸ Է ̴. vale ü  hosts  ǹѴ. ׷
  vale ̸  ̸      ִ.

   Virtual Brewery hosts   Ǿ ִ
  ִ    ̴.  Ͽ   Ư ̸ , vlager-
  if1 vlager-if2 ԵǾ ִµ, ̰͵ vlager Ǵ
  ̽ν,  ּҸ  ִ.

       #
       # Hosts file for Virtual Brewery/Virtual Winery
       #
       # IP            local        fully qualified domain name
       #
       127.0.0.1       localhost
       #
       191.72.1.1      vlager       vlager.vbrew.com
       191.72.1.1      vlager-if1
       191.72.1.2      vatout       vstout.vbrew.com
       191.72.1.3      vale         vale.vbrew.com
       #
       191.72.2.1      vlager-if2
       191.72.2.2      vbeaujolais  vbeaujolais.vbrew.com
       191.72.2.3      vbardolino   vbardolino.vbrew.com
       191.72.2.4      vchianti     vchianti.vbrew.com

    ȣƮ IP ּҿ ִ Ʈũ ȣ ɺ
  ϰ   ̴. ׷ Ǹ, hosts  /etc/networks
  ϴ    ̴.    Ʈũ ̸ Ʈũ
  ȣ ִ  Ѵ. Virtual Brewery  
  networks  ġ  ִ:

       # /etc/networks for the Virtual Brewery
       brew-net     191.72.1.0
       wine-net     191.72.2.0

  5.7.  Interface Configuration for IP

  4忡   ϵ ϰ , Ŀ  Ʈŷ
  Ʈ ˷  ġ  Ѵ. ⿡ Ʈũ
  ̽ ϰ,  ̺  ʱȭ Ű  Ѵ.
  ̷ ۾ 밳 ý õ , rc.inet1 ũƮ Ͽ 
  ȴ. ⿡ ifconfig route  Ѵ.

  ifconfig ɾ Ŀ Ʈŷ    ִ ̽
     . ׸ IP ּҿ  ٸ   Ҵ۾
  ̽ Ȱȭ Űµ  ϸ, ̷ ۾ "taking
  up"̶ θ. ⿡ Ȱȭ  Ѵٴ  Ŀ  ̽
  ؼ IP ͱ׷ ۼ Ѵٴ ǹ̴.    ̷
  ۾    ϴ   ̴.

       ifconfig interface ip-address

   ̰ ip-address interface Ҵϰ ̰ Ȱȭ  Ųٴ
  ǹ̴. ٸ    ʱⰪ ȴ. ̸׸, Ŭ B
  ּҿ شϴ 255.255.0.0  IP ּ Ʈũ  Ŭ ʱ
    ũ ϱ⵵  Ѵ. ifconfig    κп
  ϰ ٷ ̴.

  route  Ŀ  ̺ Ʈ ߰ϰų  
  ϴ  ɾ̴. ̰   Ѵ.

       route [add|del] target

  ⼭ add del target Ʈ ߰  ϴ
  ̴.

  5.7.1.  The Loopback Interface

  ù ° ϴ ̽  ̴̽.

       # ifconfig lo 127.0.0.1

  Ȥ  IP ּ ſ  ϴ ȣƮν localhost
      ̴. ifconfig hosts Ͽ  ̸ ã
  ̸,  Ͽ  ȣƮ ش ϴ IP ּ ν, 127.0.0.1
   ̴.

       # Sample /etc/hosts entry for localhost
       localhost      127.0.0.1

  ̽   ؼ, ifconfig    
  ̽    ָ ȴ:

       # ifconfig lo
       lo       Link encap Local Loopback
                inet addr 127.0.0.1  Bcast [NONE SET]  Mask 255.0.0.0
                UP BROADCAST LOOPBACK RUNNING MTU 2000 Metric 1
                RX packets 0 errors 0 dropped 0 overrun 0
                TX packets 0 errors 0 dropped 0 overrun 0

  ôٽ,  ̽ ּ 127.0.0.1 Ŭ  A Ѵ
  ʹ װ  ݸũ 255.0.0.0 ҴǾ. е
  ˴ٽ, ̽ εĳƮ ּ     Ǿ ִ.
  ·  ̰  ؼ ׸   ƴ . ,
   ȣƮ rwhod ϴ α׷ Ųٸ, rwho
   ϰ ϱ ؼ  ġ  εĳƮ ּҸ 
  ־  Ѵ. ε ĳƮ ϴ  "5.8 All about ifconfig"
   Ǿ ִ.

     Ը Ʈũ      ̴.
  ׷    ִٸ, IP ִ ü  ̺ 
  ߰ ʾҴ. 127.0.0.1̶  ּҸ Ʈ ν,
    ̽    ̴.    
    ָ ȴ.

       # route add 127.0.0.1

   ٽ,  IP ּ ſ localhost ȣƮ  
  ְ Ǿ.

  ׷ ,   ۾ ùٸ ۵ Ȯ  ƾ
  Ѵ. ̷ ۾ ping  ϸ ȴ. ping  sonar
  device ¸Դ Ʈŷ  , ־ ּҰ  Ǿ,
  ͱ׷  װ ٽ ǵ    ߻ϴ ð
  ϴ     ۾    Ѵ.  ð 밳
  "round-trip time"̶ θ.

       # ping localhost
       PING localhost (12.0.0.1): 56 data bytes
       64 bytes from 127.0.0.1: icmp_seq=0 ttl=32 time=1 ms
       64 bytes from 127.0.0.1: icmp_seq=1 ttl=32 time=0 ms
       64 bytes from 127.0.0.1: icmp_seq=2 ttl=32 time=0 ms
       ^C

       --- localhost ping statistics ---
       3 packets transmitted, 3 packets received, 0% packet loss
       round-trip min/avg/max = 0/0/1 ms

    ó, ping  , ڰ ͷƮ 
  ʴ װ  Ŷ  ̴.   Ctrl-C
  Ÿ ϰ Ǹ,   ^C ǥõȴ.

    127.0.0.1 شϴ  Ŷ ping ԰  ÿ
  ϰ ۵ǰ   ǵ Դٴ  ش.  ̰ 
  ù  Ʈũ ̽  ߴٴ  ǹѴ.

   ping ؼ      ٸ δٸ, 
   ִٴ   ǹϴ ̴. ̷ 쿡   ¹ 
  ġǰ      Ű ִ Ȯ ƶ. 
  ifconfig route  Ű ִ Ŀ   ȣȯǰ
  ִ Ȯ ƶ.  ᱹ Ŀ Ͻ Ʈŷ    ְ
   ƾ Ѵ. (/proc/net 丮  ̷   
   ִ.) route  ߸ Է ,  Ϳ "Network
  unreachable"̶ ϴ   ޽  ̴. ̷ , Ȥö
  ifconfig ο Ͱ Ȱ ּҸ Էߴ Ȯ ƶ.
    ͸ε ĵ   ȣƮ  Ʈŷ
  ø̼  ų  ִ.     rc.inet1
  ߰ Ų rc.inet1  ũƮ /etc/rcκ ǰ ִ
  Ȯ ƶ. ǰ ִٸ,  ǻ͸  Ѷ.
  ׸         ø̼  ѹ     ƶ.
  ̸׸, "telnet localhost"  telnet  ȣƮ
   õϰ  Ѵ.

  ׸,  ̽  å    Ӹƴ϶ 
   ø ǿ ǰ ִ. ׷Ƿ,  Ʈũ
  ӵǾ ׷    ġ , ׻  ̽
   ξ Ѵ.

  5.7.2.  Ethernet Interfaces

  ̴ ̽     ̽ ſ ϴ. 
     ,     ̴.

  Virtual Brewery 츮 IP Ʈũ   
  Ҵ. װ ٺ Ŭ B شϴ Ʈũ Ŭ C
  شϴ    ̷ ȯ  νĽŰ  ̽
   ؼ,    ָ ȴ.

       # ifconfig eth0 vstout netmask 255.255.255.0

  , ̰ vstout (191.72.1.2) ͳ ּҸ eth0  ̽
  Ҵϴ ۾ . ⼭  ݸũ   ʾҴٸ,
  ifconfig IP Ʈũ Ŭκ  ݸũ з   ̴.
  , ݸũ 255.255.0.0 νϴ   ϰ ȴ.

       # ifconfig eth0
       eth0    Link encap 10Mps Ethernet HWaddr 00:00:C0:90:B3:42
               inet addr 191.72.1.2 Bcast 191.72.1.255 Mask 255.255.255.0
               UP BROADCAST RUNNING MTU 1500 Metric 1
               RX packets 0 errors 0 dropped 0 overrun 0
               TX packets 0 errors 0 dropped 0 overrun 0

    ifconfig εĳƮ ּ (  Bcast)
  Ϲ    شٴ    ִ.   ȣƮ Ʈ
     ȣƮ Ʈũ ȣ̴. , message transfer
  unit (Ŀ  ̽   ִ ̴   ִ
  ũ) 1500 Ʈ  ִ밪 . ̷    Ŀ
  ϰ  Ư ɼ overrideǾ ִ.

   ۾  ϰ, ݺ   Ʈ
  ġؾ Ѵ.   ۾ eth0 ؼ Ŀο   ִ
  Ʈũ 뺸 ִ  Ѵ. Virtual Brewer  
      ִ.

       # route add -net 191.72.1.0

  route  θ ļ ̽    ̷
  ۾    𸥴: Ŀ Ǿ  ִ 
  ̽ ˻ϰ   ּ ( 쿡 191.72.1.0) ̽
  ּ  Ʈũ  κ (̽ ݸũ Ʈ κ) 񱳸
  Ѵ. ⿡ ̽  eth0 ġȴ.

  ׷, ⼭ -net ɼ ϱ? ̰ route Ʈũ 
  ο ܵ ȣ Ʈ ( ҵ ̰ localhost ȴ.)
   , ΰ ٸ óϱ    ɼ Ѵ. ּҰ
  dotted quad notation ־ , route ȣƮ κ  Ʈ
  Ʈũ κ ȣƮ κ  ̴.   ּ
  ȣƮ   0 Ǿ ִٸ, route  ּҰ Ʈũ
  Ÿ ִٰ Ѵ. ׷, route 191.72.1.0 Ʈũ ȣ
     ȣƮ ּҶ  ̴.    , route 
   ϰ  ִ     ̴. ׷Ƿ, -net ɼ
  ν, װ Ʈũ Ÿ ִٰ ϰ  ־ Ѵ.

  ,   route  ¼   ۾  ,
  öڸ ߸ ġ  츦   ִ. ̰ͺ    
  ̶, /etc/networks  Ʈũ ̸    ִ.
  ̰  ݴ б  ϱ  ̴;  -netɼ
  Ÿ   ִ. ֳϸ,  route 191.72.1.0 Ʈũ
  Ű  ٴ  ˰ ֱ ̴.

       # route add brew-net

  ݱ  ⺻ ۾ ,   ̴
  ̽   ۵ϰ ִ ˰ ʹ.  ̴ݿ
  vlager  ȣƮ ϶.

       # ping vlager
       PING vlager: 64 byte packets
       64 bytes from 191.72.1.1: icmp_seq=0, time=11. ms
       64 bytes from 191.72.1.1: icmp_seq=1, time=7. ms
       64 bytes from 191.72.1.1: icmp_seq=2, time=12. ms
       64 bytes from 191.72.1.1: icmp_seq=3, time=3. ms
       ^C

       ----vstout, vbrew.com PING Statistics----
       4 packets transmitted, 4 packets received, 0% packet loss
       round-trip (ms)  min/avg/max = 3/8/12

    ̿ ٸ  Ҵٸ, װ ý ٴ 
  ǹѴ.     Ŷ ս ġ ٸ, װ
  ϵ  ɼ .  , ͹̳Ͱ ҷ̶...
     Ŷ   ٸ, netstat ̽
  ȯ ˻ ƾ Ѵ. ifconfig Ÿ Ŷ ´
     Ŷ ޵Ǵ ˷ش.   
  ȣƮ ϰ ִٸ,    ̽ ¸ ˻ ƾ
  Ѵ. ̷  սǵ Ŷ   ִ   ִ.
  Դٰ     ȣƮ ùٸ  Ʈ  
  ִ ˾  ؼ route  ־  
  캸ƾ  . ƹ ɼǾ route ־  Ŀ 
  ̺ Ѵ. (-n ɼ ȣ Ʈ  ϴ ſ Ʈ
  еǾ ִ ּҸ ϴµ Ѵ.)

       # route -n
       Kernel routing table
       Destination  Gateway  Genmake          Flags  Metric  Ref  Use    Iface
       127.0.0.1    *        255.255.255.255  UH     1       0    112    lo
       191.72.1.0   *        255.255.255.0    U      1       0     10    eth0

  ̷ ʵ尡  ִ ǹ̴ 'Checking with netstat' 
  Ѵ. Flag  ̽  Ϸ ÷̴. U  
  Ȱ ̽ ִ  , H   ּҰ ȣƮ
  Ű  ִٴ  Ѵ.   H  ÷װ Ʈũ  Ʈ
  Ǿ ִٸ, ݵ route   -net ɼ ٿ־ Ѵ.
  Ʈ  ۵ϰ ִ ˾ƺ, Use ʵ尡   ping
  ȣ̿ ϰ ִ  Ȯ ƶ.

  5.7.3.  Routing through a Gateway

   ϳ ̴ 󿡼 ȣƮ ϴ 츦 캸Ҵ.
  Ʈ ̸    ٸ  Ǿ ִ Ʈũ  
    ̴. ̷ Ʈ  ܼϰ   ̻ ̴ݰ
  Ǿ ִ 쵵 , ͳݰ  ܺμ  Ǵ 쵵
  ִ. Ʈ̸ ϱ ؼ Ʈŷ  ߰  
    ־ Ѵ.

  ̸׸, Virtual Brewery Virtual Winery ̴ݵ vlager̶
  ϴ Ʈ ̿ Ǿ ִ. vlager ̹ Ǿ ִٰ
  . 츮  vstout   ̺  ٸ Ʈ ߰
    ֱ⸸ ϸ ȴ. ̷ ϰ Ǹ,    ̺ Ŀο
  ̾߱ ؼ, vlager  Winery Ʈũ ִ  ȣƮ 
    ְ ش. ̷ ۾ route  incantation
  Ʒ :  gw Ű     Ʈ̸ Ű ִ
   Ѵ.

       # route add wine-net gw vlager

  ,  ̾߱ ϰ  Winery Ʈũ ִ  ȣƮ
  Brewery  Ʈũ ġϴ  Ʈ ־ Ѵ.  ׷
  ,   vstout  vbardolino ͸   
  ̴.   vbardolino ƿ   ū Ŷ 
  ̴.

        ̴ ̿ Ŷ ȯϴ
  Ʈ̸  Ÿ .   vlager  SLIP ũ   ؼ
  ͳݰ  Ǿ ִٰ  .  츮 vlager óǴ
  ͱ׷ Brewery ̿  Ʈũ   ̴.  
  ۾ vstout Ʈ Ʈ̷  ν ذ  ִ.

       # route add default aw vlager

  0.0.0.0̶ ּҸ  , Ʈũ ̸ default
  ϴ  Ʈ  Ʈ Ÿ ̴.  ̸ route Ǿ
  ֱ  /etc/networks ߰ ʿ .

   ȣƮ ping , ϳ ̻ Ʈ̸  ġ鼭 Ŷ
  Ŵ ս ߻ȴٸ,  ȥ Ʈũ ִٴ  ǹѴ.
  Ŷ ս      Ͻ   ߻ϴ
  ̴. ׷    Ͱ ǰų  ҵǱ⵵ Ѵ.

  5.7.4.  Configuring a Gateway

    ̴ ̿ Ŷ ȯϱ  ǻ͸  ϴ ۾
  ſ ϴ.  ٽ, vlager ƿͼ ̰   ̴ 带
  ߰ ,     ϳ Ʈũ ϰ ִٰ .
    ̽  ־  ϸ,  ̽
  װ͵鸸 IP ּҸ Ҵ ־ Ѵ.

    ̽    Ʒ   hosts Ͽ
  ߰ ִ  ϴ. ׷ Ǹ,  ̽ ̸
  ο ִ ۾    ̴:

       191.72.1.1      vlager       vlager.vbrew.com
       191.72.1.1      vlager-if1
       191.72.2.1      vlager-if2

        ̽    ִ:

       # ifconfig eth0 vlager-if1
       # ifconfig eth1 vlager-if2
       # route add brew-net
       # route add wine-net

  5.7.5.  The PLIP Interface

    ǻ͸ PLIP ũ ų ̴    ؾ ϴ
  ۾ ణ  .  εĳƮ Ʈũʹ  ݴ,
     ȣƮ ױ    point-to-point ҷ.

   , Virtual Brewery ִ   ٷڵ ׵ 
  ǻ͸ PLIP  ؼ vlager Ѵٰ .   ü
  vlite θ, PLIP  ϳ з Ʈ ʿϴ.
  ýÿ,  Ʈ plip1 ϵ ̴.  ũ Ȱȭ Ű
  ؼ,    ؼ,  plip1 ̽ 
  ־ Ѵ.

       # ifconfig plip1 vlite pointopoint vlager
       # route add default gw vlager

  ù ° ɾ ̽ ϴ ̴. ,  vlager ּҸ
   ִ   ּҷ point-to-point  Ѵٰ Ŀο
  ִ  Ѵ. ׸  ° ɾ Ʈ   ϴ
  vlager ؼ  Ʈ Ʈ ġϴ  ̴.  vlager󿡼,
  ifconfig ϴ  ũ ȰȭŰ    ʿϴ. (route
    ʿ  ʴ.):

       # ifconfig plip1 vlager pointopoint vlite

  ̷ο  vlager ִ plip1 ̽  IP ּҸ  
  ־  ʿ    191.72.1.1̶ ּҸ  
   ִ.

   츮  ǻͿ Brewery Ʈũ θ  ־
  Ѵ; Brewery ȣƮ vlite θ ϴ  
  κ ִ. ణ   ,  ȣƮ   ̺
  vlager̸  Ʈ̸ vlite ٽ θ  ִ ̴:

       # route add vlite gw vlager

  ӽ Ʈ  , ׿    ذåδ 
   ϴ  ִ.     йϱ
  ؼ   Ʈũ ִ ȣƮ    gated
  ġؾ Ѵ. ׷ ʱ  proxy ARP ߾.  ״,
  proxy ARP  ִ vlager  ü ̴ ּҸ ν,
  vlite   ARP ǿ    ־.  ̷ ȿ
  vlite  ִ  Ŷ vlager Ϻϰ ۵ǰ, ׷ 
  Ŷ  ǻͷ ٽ ۵  ־.  proxy ARP  ڼ
  ׵ 'Checking tht ARP Tables' ٷ .

  ̷ Net-3  plipconfig ϴ   ̴. 
      Ʈ IRQ   ֵ  ش.
  ¼ ̰ Ϲ  ϴ ifconfig  ſ  
   ̴.

  5.7.6.  The SLIP and PPP Interface

   SLIP PPP ũ PLIP    ó ܼϰ point-to-point
  ũ ϰ ,  ΰ  ̾߱     .
  밳, SLIP  ϱ  ؼ    ؼ
   ̾  ؾϰ, SLIP 忡 °  ø 
   ־ Ѵ. PPP ܼ ࿡  ȴ. SLIP PPP
  ũ    ʿ  7 8忡 ڼ ϰڴ.

  5.7.7.  The Dummy Interface

   ̽  ٸ  ſ ϰ δ. ̰
  ĵ ȣƮ  IP Ʈũ ؼ ̾  ũ 
  ش.  ڵ ĵ ȣƮ    ִ.

  ĵ  ȣƮ ܵ Ʈũ ġ 밳 ּҰ 127.0.0.1
  Ҵ   ġ Ȱȭ Ű  Ѵ.  쿡, 
   ȣƮ   IP ּ  ͸  ʿ䵵 ִ. ̸׸,
  vlite ϴ  ǻͰ ִٰ   .  װ 
  Ǿ ִ  Ʈũ   쵵 ִ. vlite ִ 
  ø̼  ȣƮ ִ  ٸ ø̼ 
  ͸   ;   𸥴. /etc/hosts ִ  vlite
  191.72.1.65 IP  ּҸ  ã ,   ̼  ּҷ
  ͸  õ ̴.  ǻͿ Ȱȭ 
  ,  ̽ۿ ,  Ŀ  ּҰ 
  ̽   ִ  Ѵ.   , Ŀ
   ͱ׷ óϰ  ø ̼   
  ̴.

  ̷   ̽ ʿϴ. ̰   ̽
    ν ̷  ذ ش. vlite 쿡,
   ܼ 191.72.1.65 ּҸ Ҵ ְ, ȣƮ Ʈ
   ּҸ Ű  ֱ⸸ ϸ ȴ.

  191.72.1.65   ͱ׷  ۵ ̴.

       # ifconfig dummy vlite
       # route add vlite

  5.8.  All About ifconfig

  ifconfig 츮   ͺ ξ    ִ.
  Ϲ ϴ ɼδ    ִ.

       ifconfig interface [[-net | -host] address [parameters]]

  interface ̽ ̰, address ̽  Ҵ IP
  ̴ּ. dotted quad notation ǥǾ ִ IP ּҳ  ̸
  ifconfig /etc/hosts /etc/networks  ã ̴. -net -host
  ɼ  ifconfig Ʈũ ȣ ȣƮ ּҸ   ּҷ ٷ
   Ѵ.

   ifconfig  ̽ ̸  ִٸ, װ
  ̽ ȯ  Ÿ ̴. ƹ   ifconfig
  ԷϿ ,      ̽ Ÿ ̴; -a
  ɼ Ȱϰ    ̽    ̴. ̴
  ̽ eth0    ̴:

       # ifconfig eth0
       eth0     Link encap 10Mbps Ethernet HWaddr 00:00:C0:90:B3:42
                inet addr 191.72.1.2 Bcast 191.72.1.255 Mask 255.255.255.0
                UP BROADCAST RUNNING  MTU 1500  Metric 0
                RX packets 3136 errors 217 dropped 7 overrun 26
                TX packets 1752 errors 25 dropped 0 overrun 0

  MTU Metric ʵ  MTU ̽ Ͱ  (metric value)
  ش.  Ͱ (metric value)  Ʈ   ϱ
     ü ؼ Ǿ.  ̷  
  , ȣȯ  ֱ ϴ.

  RX TX  󸶳  Ŷ ް ִ, ۵Ǿ, 󸶳
      ߴ, Ǵ ޸  󸶳   
  Ŷ սǵǾ,    󸶳  ذ ִ
  ش. ù  (receiver  overrun) 밳 Ŀ ͷƮ
  Ŵ ӵ Ŷ    ۵   ߻Ѵ. Ʒ 
  ifconfig  ִ ɼ ְ ,  ɼ ϴ
  ΰ Ÿ ְ  ִ.̷  ɼ ׻ ifconfig  (-)
  뽬 ٿ Ѵ.

     UP ̰ ̽ "up"϶ ǥ̴. , IP  (layer)
        ٰϰ   Ѵ.  ɼ address ɾ
        ־  ȴ. ̰  ̽   ̸,
        ̰ down ɼ  Ͻ 밡ϰ  ش.  (
        ɼ UP RUNNING ÷׿ ġѴ.)

     down
        ̰ ̽ "down"϶ ǥ̴. , IP (layer)
         ϰ   Ѵ. ̰    ̽
        ؼ   IP Ʈ   ϰ . ̰ 
        ̽ ڵ   ְ ִ  
        Ʈ   ƴ  ζ.   
        ̽    ϰ  ̶, ̷
         Ʈ  ÿ, θ  ־ Ѵ.

     netmask mask
        ̰ ̽ ǰ ִ   Ҵ ش.
        ̰ 0x  32Ʈ 16 ǥϰų, Ʈ ϴ 
          ǥ .

     pointopoint address
         ɼ   ȣƮ point-to-point IP ũ 
        ȴ.   SLIP Ǵ PLIP ̽   
        ɼ ʿ ϴ.  ( point-to-point ּҰ Ǿ ִٸ,
        ifconfig  POINTOPOINT ÷׸ ǥ  ̴.)

     broadcast address
        εĳƮ ּҴ 밳 ȣƮ  κ  Ʈ 
        , Ʈũ ȣ Ѵ.  IP implementation ٸ
        Ű  Ѵ;   ɼ  ̷ ̻ ȯ  
        ְ ش. ( εĳƮ ּҰ Ǿ ִٸ,
        ifconfig BROADCAST ÷׸ ǥ   ̴.)

     metric number
         ɼ ̽   ̺ Ʈ Ͱ
        Ҵϴµ  𸥴.  metric Ʈũ 
         ̺   Routing Information Protocol (RIP)
         ȴ.  ifconfig Ǵ Ʈ Ͱ 0̴. 
         RIP   ʰ ִٸ,  ɼ 
        ʿ  ;  RIP  ״ٸ,  Ͱ  
        ų ʿ  .

     mtu bytes
        ̰ Maximum Transmission Unit,   ̽ ϳ 
        Ʈǿ ó  ִ ִ ݼ    Ѵ.
        ̴ݿ MTU Ʈ 1500̸, SLIP ̽ 296
        ȴ.

     arp
        ̰ ̴̳ Ŷ   εĳƮ Ʈũ
        ϴµ  ϴ ɼ̴. ̰  ȣƮ 
        ּҰ Ʈũ ϴ  س   Ǵ ARP,
        Address  Resolution Protocol   ְ ش. ε
        ĳƮ󿡼 Ʈ Ǿ ִ.  (ARP ϰ 
        ʴٸ, ifconfig NOARP ǥ  ̴.)

     -arp
        ̽ ARP     ִ ɼ̴.

     promisc
        promiscuous  ̽ ش. εĳƮ
        Ʈũ󿡼, ̰ Ŷ ٸ ȣƮ  
        ұϰ,   Ŷ ޾ ִ ̽   ش.
        ̰  Ʈũ Ʈ  Ethernet snooping  Ŷ
        ͸   ְԲ  ش. 밳  ɼ Ʈũ
         ذϴ  ̴ ٸ , ̰ Ĩڵ
         н带 ˾Ƴ  Ʈũ  Ʈ ѱų
        ٸ   ϰ   ִ. ̷ ĨԿ ϴ 
        δ  ǻͷ Ĩڵ     Բ
        ϴ  ̴. Kerberos SRA    ϴ
        ̴. ( ɼ PROMISC ġѴ.)

     -promisc
        promiscuous 带  ´.

     allmulti
        ƼĳƮ ּҴ  ݿ  ʿ䰡  ȣƮ ׷
        εĳƮѴ. ƼĳƮ ּҴ  Ŀο 
        ʴ´. (  ɼ ALLMULTI ÷׿ ġѴ.)

     -allmulti
        ƼĳƮ ּҸ  ʰ Ѵ.

  5.9.  Checking with netstat

  ,   Ʈũ ȯ ˻ϰ Ȱȭ ų  
  ϰ ϴ    ̴. ̰ netstat θ,
       Բ Ѵ.    ɵ 
  ϰڴ.

  5.9.1.  Displaying the Routing Table

  -r ÷׿ netstat  ϰ Ǹ,  route  
   Ŀ  ̺ ǥ ش. vstout 
   Ÿ:

       # netstat -nr
       Kernel routing table
       Destination    Gateway     Genmask          Flags  Metric Ref Use  Iface
       127.0.0.1      *           255.255.255.255  UH     1      0    50  lo
       191.72.1.0     *           255.255.255.0    U      1      0   478  eth0
       191.72.2.0     *           255.255.255.0    UGN    1      0   250  eth0

  -n ɼ netstat ɺ  ȣƮ Ʈũ ̸ſ Ʈ
  е   IP ڷ ּҸ ǥϰԲ ش. ̰ 
  Ʈũ ؼ ּҸ ã ۾ ϰ   ϰ ȴ.
  ( , DNS Ǵ NIS )

  netstat ¿  °  Į Ʈ̰  Ʈ
  Ű ִ ش.  Ʈ̸ ϰ  ʴٸ,
    ƽƮ  (*) ǥõ .      Į
  Ʈ "Ϲݼ(generality)"  ش. ־ IP ּҰ ׿
   Ʈ ߰ , Ŀ   ̺ Ʈ
  ļ, genmask   Ʈ AND ڷ Ѵ.

   ° Į Ʒ    ÷ ǥ ش:

     G  Ʈ Ʈ̸ Ѵ.

     U  ̽ ǰ ִ.

     H   ܵ ȣƮ Ʈ ļ   ִ.  ,
        ̷   Ʈ 127.0.0.1̴.

     D  ̺ Ʈ  , ICMP ̷Ʈ ޽ 
        ǰ ִ.

     M  ̺ Ʈ  , ICMP ̷Ʈ ޽ 
        ǰ ִ.

  netstat ¿ Ref Į   Ʈ ϴ ȣ Ÿ.
  , 󸶳  Ʈ  Ʈ ϰ ִ Ÿ.
     Į  Ʈ  Ǿ, 󸶳  
  ׷ ̽ ۵Ǿ Ÿش.

  5.9.2.  Displaying Interface Statistics

  -i ÷׿ netstat Բ ϸ,  Ǿ ִ Ʈũ
  ̽ ¸ ش. ű⿡ ٰ -a ÷׸ ְ Ǹ,
  Ŀο ϴ  Ӹ ƴ϶,   Ǿ ִ  ̽
    ̴. vstout, netstat   :

       $ netstat -i
       Kernel Interface table
       Iface  Mtu  Met    RX-OK RX-ERR   RX-DRP RX-OVR  TX-OK   TX-ERR
  TX-DRP TX-OVR Flags
       lo       0   0    3185      0      0      0   3185      0      0      0 BLRU
       eth0  1500   0  972633     17     20    120 628711    217      0      0 BRU

  MTU Met ʵ ̽   MTU Ͱ (metric   value)
  ش. RX  TX Į 󸶳   Ŷ   ۵ǰ
    (RX-OK/TX-OK), ׸ ջ Ծ    (RX-ERR/TX-ERR),
  󸶳            Ŷ     ҵǾ (RX-DRP/TX-DRP),
     սǵ  󸶳 Ǵ (RX-OVR/TX-OVR) Ÿ
  ش.

   Į ̷ ̽  Ǿ  Ÿִ
  ÷̴.     ÷ ̸  ifconfig
  ̽ ȯ   µȴ.

     B  εĳƮ ּҰ Ǿ ִ.

     L   ̽ Ʈ ̴̽.

     M   Ŷ ۵ǰ ִ. (promiscuous )

     N  Trailer Ѵ.

     O   ̽  ARP  ִ.

     P  ̰ point-to-point ̴.

     R  ̽ ǰ ִ.

     U  ̽ up

  5.9.3.  Displaying Connections

  netstat Ȱϰ ִ  ǥ  ֱ  ɼ   ִ.
  -t, -u, -w ׸, -x ɼ Ȱ TCP, UDP,  RAW Ǵ UNIX  
   ش. ⿡ -a ɼ  ߰Ѵٸ,   ٸ
   ǥ ش.   ýۿ   ǰ ִ 
      ̴.

  vlager netstat -ta   ȭ Ѵ.

       $ netstat -ta
       Active Internet connections
       Proto  Recv-Q  Send-Q  Local Address    Foreign Address     (State)
       tcp         0       0  *:domain         *:*                 LISTEN
       tcp         0       0  *:time           *:*                 LISTEN
       tcp         0       0  *:smtp           *:*                 LISTEN
       tcp         0       0  vlager:smtp      vbardolino:1040     ESTABLISHED
       tcp         0       0  *:telnet         *:*                 LISTEN
       tcp         0       0  localhost:1046   vbardolino:telnet   ESTABLISHED
       tcp         0       0  *:chargen        *:*                 LISTEN
       tcp         0       0  *:daytime        *:*                 LISTEN
       tcp         0       0  *:discard        *:*                 LISTEN
       tcp         0       0  *:echo           *:*                 LISTEN
       tcp         0       0  *:shell          *:*                 LISTEN
       tcp         0       0  *:login          *:*                 LISTEN

  ̰ 밳  ٸ   ش.   °
   vstout  SMTP ش. ׸   °
   vbardolino telnet ̿ ܺο  Ÿ.

  -a ÷׸ ϸ,     ش.

  5.10.  Checking the ARP Tables

   쿡 Ŀ ARP ̺  ų Ű  
   ִ.   ,    ͳ ּҰ ϳ  ִٰ
  ǽϴ ,   Ʈũ  ߻ų  ִ. ̷
   ذϱ    ٷ arp̴.  ࿡ ɼ
    δ.

       arp [-v] [-t hwtype] -a [hostname]
       arp [-v] [-t hwtype] -a hostname hwaddr
       arp [-v] -d hostname [hostname...]

   hostname  ɺ ȣƮ ̳  dotted quad notation
  ǥ IP  Ҹ ϴ ̴.

  ù °   װ no hostname ־ٸ, ˷  
  ȣƮ IP ּ ׸ Ư ȣƮ ARP Ʈ ش. 
  , vlager arp  ϰ Ǹ    Ÿ.

       # arp -a
       IP address       HW type                   HW address
       191.72.1.3       10Mbps Ethernet           00:00:C0:5A:42:C1
       191.72.1.2       10Mbps Ethernet           00:00:C0:90:B3:42
       191.72.2.4       10Mbps Ethernet           00:00:C0:04:69:AA

  vlager, vstout ׸ vale ̴ ּҸ ְ ִ.

  -t ɼ ϸ, Ư   ϵ    ִ.
  ̰  ether, ax25, Ǵ pronet, 10Mbps ̴ ⺻
  ϰִ ϵ, AMPR AX.25,   IEEE 802.5 token ring 
  ϵ   ִ.

  -s ɼ ARP ̺ hostname ̴ ּҸ  ߰Ű
      . hwaddr  ϵ ּҸ Ѵ. ⺻δ
  ̴ ּҸ Ÿ. ׸  ̰  ݷ (:)  Ǿ
  ִ   16  Ǿ ִ.  ¼ -t ɼ
  ؼ, ٸ  ϵ ּҸ   ִ.

   ȣƮ ARP Ǹ źϴ 쿡, ARP ̺ IP ּҸ
    ֶ ޽ . ̷  ߻ϴ
  ̶, ARP ̹ װ ߻ ߴٴ, ȣƮ IP ּҸ
  ߸ ν Ʈũ  ٸ ȣƮ   ̷ 
  ߻Ѵ. ARP ̺ ִ hard-wiring IP ּҴ  ̴
  󿡼   ȣƮ ȣ  ִ ̴.

  -d ġ Բ arp ϰ  Ǹ, ־ ȣƮ Ǿ  ִ
   ARP Ʈ   . ̰ ̽ Ͽ 
  ǰ ִ IP ּҿ  ̴  ּҸ Բ ϱ 
  õ ϴµ Ǳ⵵  Ѵ. ̰  ߸ Ǿ ִ
  ý ߸ ARP  εĳƮϴµ ϰ δ. (
   ̷ ۾ ϱ ,   ȣƮ 籸ؾ Ѵ.)

  -s ɼ proxy ARP  ϴµ ȴ.  ̰ gate  ϴ
  ȣƮ  fnord ϴ  ٸ ȣƮ  Ʈ̷ ۵ϵ
   ִ ν,    ּҰ ̸Ͽ gate ϴ 
  ȣƮ ϵ   ش. , װ   ü ̴
  ̽ Ű fnord  ARP  Ʈ ν ׷
    ִ. ȣƮ fnord  ARP Ǹ   , gate
  ̴ ּҸ  ϰ ִ  ǵ  ̴. Ǹ ϰ ִ
  ȣƮ gate  ͱ׷     ǹ
  fnord  ڷ  ̴.

  ̸׸,  TCP  ϰ, õ ״ 
  ϴ DOS  ſ fnord ϰ   ̷  
  ʿϴ.  proxy ARP Ѵٸ, ġ fnord  ݿ
  ִ ó,   DOS ӽſ  ó   ̴. ׷,
  Ʈ̸  Ʈ ϴ  ʿ䰡 .

  proxy ARP ſ ϰ   ִ   ٸ ø̼
  ִ. ,  ̾  ũ ؼ,  ȣƮ  Ͻ
  Ʈó ϰ  ִ ̴. ,  츮 ̵
  PLIP  ũ ļ, vlager  Ǿ ִ  vlite Ҵ. 
   proxy ARP ϰ ϴ ȣƮ ּҴ Ʈ 
  ִ   󿡼  ̴. ̸׸, proxy ARP ϰ
  ִ vstout  Brewery  (191.72.1.0) ȣƮ  
  , Winery  (191.72.2.0)   ȣƮ   .

  fnord proxy ARP ϴ    ;   gate
  ̴  Ҹ  ־ Ѵ.

       # arp -s fnord 00:00:c0:a1:42:e0 pub

     proxy ARP Ʈ   ִ.

       # arp -d fnord

  5.11.  The Future

   Ʈŷ  ȭϰ ִ. Ŀο ֿ ȭ Ѵٸ,
  ȯ   ſ ϰ ų  ִٴ ̴. , Ŀ
   ð Ʈũ  ġ ϰ ش. ̸ ׸,
  ifconfig  IRQ DMA  äΰ    ش.

   ٸ ȭ Ѵٸ, route ɿ mtu ÷׸ ߰ Ų ̴.
    Ư  Ʈ  ִ   (Maximum Transmission
  Unit)     ִ.  MTU  Ʈ ̽
  õǾ ִ MTU ȿȭ  ų  ִ.   
  Ʈ̿ ſ  MTU ʿ ϴ  ȣƮ ϰ  ,
  Ʈ̸  Ʈ Ҷ,  ɼ  ̴. 
  , ȣƮ wanderer SLIP ũ ؼ vlager Ǿ ִٰ
  . vstout wanderer  ͸   , wanderer
  ִ Ʈŷ  (layer) Ŷ ̴  ļ  ,
  ְ 1500 Ʈ Ŷ  ̴. , SLIP ũ 296   Ʈ
  MTU Ǿ ϰ, vlager Ʈũ   IP Ŷ 296
  Ʈ ɰ   Ѵ. ſ  vstout Ʈ
   , ۽ 296 Ʈ MTU  ϰԲ  Ҵٸ,
          ִ.

       # route add wanderer gw vlager mtu 296

      ִ mtu ɼǶ 'Subnet  Are Local' å
  (SNARL)   ҵǾٴ  ϶.  å Ŀ ȯ 
  ɼǿ  ־,  3 忡 ߾.

  6.  Name Service and Resolver Configuration

  2忡  ٴ, TCP/IP Ʈŷ ȣƮ IP ּҸ
  ȯϱ    Ű ϰ ִ.   
  /etc/hosts Ǿ ִ ȣƮ  ̺ ̸  
  ɰ  ƹ ̵    Ѵ.   
   ѻ  Ǹ, ܺμ  ƹ IP Ʈ ߻
    Ը  LAN ϴ. hosts   ̹ 5忡
  Ͽ.

  ٸ ,  ȣƮ IP ּҷ ȯų  Ǵ
  BIND - Berkeley Internet Name Domain Service    ִ.
  BIND ϴ      , Ʈũ 
   ,  ѹ ؾ ۾̴.    ٸ н 迭
  ýۿ,  񽺴 named α׷   ȴ.
  õ, ̰  ϵ  ü (cache) ϰ,
  Ʈ Ǵ    μ Ǹ ٸ.  BIND
  ϴ     ,  ȣƮ   
  ʿ .

   忡      ⺻ĸ ٷ ̴. 
    LAN̻ ȯ̳, ͳݻ󿡼 BIND 
  ȹ̶,   , Cricket Liu "DNS and BIND" ([AlbitzLiu92]
  ϶.) ,   å о ƾ    . ̷ 
  ؼ,   BIND ҽ ԵǾ  ִ release notes Ȯ
   ִ.  comp.protocols.tcp-ip.domains̶ ϴ DNS 
  ׷쵵 ִ.

  6.1.  The Resolver Library

  "the resolver" Ư ø̼ ƴ϶ "resolver library"
  Īϴ ̴. ̰  C ̺귯   ΰ ִ 
  ̴. ߽ Ǵ  ƾδ ȣ Ʈ  ִ  IP ּҸ
  ãų IP ּҿ ִ  ȣƮ ãִ gethostbyname(2)
  gethostbyaddr(2)   ִ. ̰͵ ܼ hosts ִ 
  ãų,    ϰų, NIS (Network Information
  Service)  hosts  ͺ̽ ϵ Ǿ ִ.  smail
   ø̼  ̷ ͵  ̹   ,
  ̰ Ư 쿡 ʿϴ.

  6.1.1.  The host.conf File

   resolver ¾ ϴ   ٷ host.conf ̴.
  ̰ /etc  丮  ְ, resolver  񽺸  ָ,
  ׷ 񽺵  Ǿ ִ.

  host.conf ִ ɼǵ     ο Ѵ. ʵ
  ̽  еǾ ִ. ؽ ǥ (#) Ǿ ִ   
     ɼǿ   ª  ִ κ̴.

    ɼ ִ:

     order
        ̰ resolving service óǴ  Ѵ. ̿ Բ
        Ǵ ɼδ bind, hosts, nis ִµ,  ϴ 
          Ǹ Ѵٵ, /etc/hosts  ã´ٵ,
        NIS ʿ  ã   Ѵ. ̷ ͵   
        Ȥ θ   ִ. ο Ÿ   
        񽺰 óǴ   ǹѴ.

     multi
        ɼ   ְ Ǵ    . /etc/hosts
        ִ ϳ ȣƮ  IP ּҸ Բ ҷ, 밳
        "multihomed"  Ѵ.   ÷״ DNS NIS ǿ ƹ
         ġ ʴ´.

     nospoof
        5忡  ٴ,   DNS in-addr.arpa 
        ؼ, IP ּҿ شϴ ȣƮ  ã ش. 
          ߸ ȣƮ  ϴ  "spoofing"
        Ѵ. ̷    ؼ, resolver  IP ּҰ
        ȣƮӰ Ǿ ִ ˻ϵ Ǿ ִ. ׷
        ʴٸ, ȣƮ   ߻ų ̴. ̷  ۾
        ؼ nospoof  ƾ Ѵ.

     alert
         ɼ    ְ ϰų    . 
        ɼ on  , spoof  õ (attempt) resolver
        syslog ޽ ϵ   .

     trim
         ɼ     Ѵ. ,  
         Ͼ   ȣƮӿ  ̴. ̰
        hosts  Ʈ ϰ Ҷ ϰ  δ.  hosts
        Ʈ      ȣƮ  ϰ 
        , Ǵ  ̴.  ȣƮ ߰ پ ִ  
          ǰ, /etc/hosts ̷ ۾ 
        ̴.

     trim
        ɼ  ȣƮ    ϰԲ 
        ش.

   vlager  ̴;

       # /etc/host.conf
       # We have named running, but no NIS (yet)
       order   bind hosts
       # Allow multiple addrs
       multi on
       # Guard against spoof attempts
       nospoof on
       # Tirm local domain (not really necessary).
       trim   vbrew.com.

  6.1.2.  Resolver Environment Variables

  host.conf ϴ κ     ȯ溯 ִ.

     RESOLV_HOST_CONF
        ̰ /etc/host.conf ſ о   Ѵ.

     RESOLV_SERV_ORDER
        host.conf ־   . hosts, bind ׸
        nis ־ 񽺵 ̽, ޸, ݷ Ǵ 
        ݷ еǾ  .

     RESOLV_SPOOF_CHECK
        ־ spoofing Ұ Ѵ.     
        ҷ,  ڿ off ٿ. spoof ˻縦 ϵ 
        ִ warn warn off  α  (logging on) α 
        (logging off) Ѵ. *  spoof üũϰڴٴ ǹ,
        host.conf  , α  ʴ´.

     RESOLV_MULTI
        on Ǵ off  host.conf multi ɼ   
           ִ.

     RESOLV_OVERRIDE_TRIM_DOMAINS
         ȯ host.conf     Ʈ  
        Ѵ.

     RESOLV_ADD_TRIM_DOMAINS
         ȯ host.conf ߰ Ʈ    Ѵ.

  6.1.3.  Configuring Name Server Lookups -- resolv.conf

   ȣƮ   BIND  񽺸 ϱ ؼ,
  resolver library   Ϸ Ѵٸ, ҷ Ӽ 
  ־ Ѵ. ̷ ۾ ϱ  ؼ resolv.conf ؾ Ѵ.
    ų  Ͼ ֺ ִٸ,  resolver   
    ȣƮ ִٰ  .

     ȣƮ Ӽ Ϸ Ѵٸ, 
   ־  Ѵ. ׷,  Ʈũ Ӽ ϰ
  ִٸ, ̰ ϴ  ξ  ̴.

  resolv.conf  ߿ ɼ nameserver̴. ̰ 
  Ӽ IP  Ҹ Ҵ ִ  Ѵ.  
  nameserver ɼ ؼ     ϰ Ѵٸ,
  װ͵ ־  óȴ. ,      ϴ
   . ,   ִ Ӽ   .

  no nameserver ־ٸ, resolver  ȣƮ ִ Ӽ
  Ϸ  ̴.

  domain search ɼ Ѵ Ʈ  ÿ ȴ. ,
  BIND ù ° ǰ ߴٸ, ̷ ɼǵ ȣƮӿ
  . search ɼ   õ ҷ  
  Ѵ.  ׸ ̽  еǾ ִ.

  no search ɼ ־ٸ,  ü   ؼ, 
     Ʈ ġ Ʈ  , ְ Ʈ
  θ  ߰ȴ.     domain  ؼ
    ִ;  ƹ͵  ʴ´ٸ, resolver
  getdomainname(2) ý  ؼ    ̴.

   ̷   ϰ  鸰ٸ, Virtual Brewery
  resolv.conf  ϴ   :

       # /etc/resolv.conf
       # Our domain
       domain            vbrew.com
       #
       # We use vlager as central nameserver:
       nameserver      191.72.1.1

  vale ̸ resolvϷ  , resolver vale.vbrew.com
  vale.com  vale  ϴ ̸  ã ̴.

  6.1.4.  Resolver Robustness

    Ŵ Ʈũ LAN Ϸ Ѵٸ, ߾ 
   ؾ Ѵ. ̰ ϴ ̶,  ǰ 
   (cache)    Ҹ    ִٴ
  ̴.  ̷ Ű  ִ:  麻 
  ıǾ ,   LAN ƹ ۾    . ֳϸ,
  resolver  ̻ Ӽ     ̴. ׸ X
  ͹̳ο   ,  ͵    ȴ.

  ķ۽ 麻 İǴ  ſ 幮 ,  ̷ 츦
  ؼ ġ   δ ͵  ̴.

   Ӽ ϱ  Ѱ ɼδ  
  Ӽ  ȣƮ  resolv϶. ׸ ٸ ȣƮ 
   Ǹ    ϰ ϶.    ü 
  ϰ ִٸ, ̰    ̴.

  ٸ , /etc/hosts ִ  ̳ LAN   
  ȣƮ     ִ.  ߾   ٿǴ 츦
  ؼ, resolver ȣƮ  Ű ʵ ҷ,
  /etc/host.conf "order bind hosts" ߰Ѷ.

  6.2.  Running named

  κ н 迭 ýۿ    񽺸   ִ
  α׷ named (밳 name-dee Ѵ.)̴. ̰ 
  BSD ߵǾ, Ŭ̾Ʈ Ӽ񽺸  ְ,  ٸ
  Ӽ   ְԲ ش.  κ   
  ǰ ִ  BIND-4.8.3̴. ֱ  BIND-4.9.3 
  Ÿ ׽Ʈ ̰,  ϳ    
  ̴.

    Domain Name System  ۵Ǵ ؽŰ κ̴.
       κ ´ٸ, 2 ٽ ѹ о ٶ.
    DNS  ⺻     ִ.

  named 밳 ý õ  , ۵Ǹ, ý ˴ٿ  Ǳ
   ۵Ѵ.  /etc/named.boot  Ͽ ̷  
   ,  Ͽ    ּҿ ų  ϴ zone
  ̶ ϵ ԵǾ ִ. ̷   İ ǹ̴ 
  Ǿ ִ.

  named Ű ؼ, Ʈ ܼ   ϶.

       # /usr/sbin/named

  named named.boot   õǾ ִ zone  а,
   ̴.  װ μ id ASCII· /var/run/named.pid
   , ʿϴٸ,  ̸Ӹ κ ۹ 
  , DNS Ǹ  Ʈ 53    .
  6.2.1.  The named.boot File

  named.boot ũ 밳 ű ۰, ԵǾ ִ  ׸
   , zone    ϰ ִ  ϰ  ٸ
    Ű ִ. Ʈ  Ͽ  ݷ ϴ
     Ѵٴ ǹ̴. ڼ  ؼ
  named.boot  ϱ , ׸ 6.1 ־ vlager 
      캸.

       ;
       ; /etc/named.boot file for vlager.vbrew.com
       ;
       directory       /var/named
       ;
       ;            domain                  file
       ;----------------------------------------------
       cache        .                       named.ca
       primary      vbrew.com               named.hosts
       primary      0.0.127.in-addr.arpa    named.local
       primary      72.191.in-addr.arpa     named.rev

                  ׸ 6.1: vlager  named.boot

    cache primary named  Ű ̴. 
    ° 忡 õǾ ִ  Ϸκ о δ.
  װ͵ ؽƮ    ִ DNS ڿ ڸ ϰ ,
    ̴.

   , 츮     named  Ͽ.
  ̸׸, ̵  ù °  ̸Ӹ  vbrew.com
  Ȱϵ named 뺸,   named.hosts Ͽ  zone
  ͸  о δ.  directory   Ű  zone 
  /var/named ġϰ ִٴ  ش.

  cache ſ Ư ν, Ӽ ϰ ִ  踦
   ǥ Ѵ. ̰ named   ü ҿ named.ca
   (cache)Ϸκ root name server hints   ְԲ
  ش. name server  hint ؼ   ϰڴ.

    named.boot   ִ  ߿ ɼ
  ϵ̴.

     directory
        ̰ zone  ϰ ִ 丮 Ѵ.  ϵ
        ̸  丮 Ǿ ־.   丮
        directory  ν   ִ. ǥ 
        Ͻýۿ /var/named Ǿ Ѵ.

     primary
        ̰ ν domain name file name  Ѵ. named
                ϶. ̸Ӹ
        , named ־  Ϸ  zone 
        Ų. Ϲ,  Ʈ Ͽ  ϳ primary
        Ʈ   ̴. , 127.0.0.0 Ʈũ ȯŰ,
          Ʈũ  ̴.

     secondary
        ̰ ν, domain name address  list ׸ file name
         .    õ    ° 
         ȯ ´.  °  ο ִ  
        ͸   , Ͽ ڷḦ     Ѵ.
         ̸Ӹ  κ ڷḦ ۹  ̴.
        ̸Ӹ  ִ IP ּ  ϳ named ־
        Ѵ.    ͸ zone ͺ̽ 
         ,  ּҿ  ̸,  °  ־
         Ͽ Ǿ  ִ.   ̸Ӹ  
        ʴ´ٸ, zone ʹ ſ Ͽ   ˻
        ̴.  named Ģ  zone  ͸ 
        ̴. ̰  SOA ڿ ڵ · Ǿ 
          ִ.

     cache
        ̰ domain name file name ν Ѵ.  
        root server hint ϰ ,   ڵ  Ʈ
        Ӽ Ű Ǿ ִ.  NS Aڵ尡 νĵ
        ̴. domain  Ϲ Ʈ   Īϴ
        ̴.   named  ̴:  cache 
        Ʈ Ͽ ߻ ʾҴٸ, named  ̻  Ҹ
         ʴ´.   Ǹ     Ʈũ
        ϰ  ʴٸ, ̰ ׷ ۾ ߴܽ 
        ̰, Ʈũ  ۾ ϰ  ų  ̴. Դٰ
        named  Ʈ      ̰, ׸Ͽ,
           ϰ  ּҵ ذ (resolve) 
        ̴. ̷ Ģ ܰ ִٸ, װ  
           ̴. (Ʒ ִ forwarders ɼ)

     forwarders
        ̰ ν address list Ѵ.  Ͽ ִ IP
        ּҵ   ҿ ϴ  з 
        ٸ, named         Ѵ.
        ̰͵ ǿ ϴ  ϳ    ̷
        ۾ Ѵ.

     slave
        ̰   slave   ش.  ü
        Ǹ   , forwarders  Ἥ, õ 
        Ǹ ϰ   .

  ⿡ Ǿ  , sortlist domain   ɼ 
  ִ. ߰ zone  Ͽ Ǵ   ñⰡ ִ.
  װ͵ $INCLUDE $ORIGIN.  ̴. ̰͵  ʿ  
   ⼭  ʾҴ.

  6.2.2.  The DNS Database Files

  named.hosts  named  ԵǾ ִ   ׻
  origin̶ θ Ͱ Ǿ ִ   ִ. origin
  cache primary     ̴.  
  Ͼȿ,  ΰ õǾ ִ ΰ ȣƮ  ؾ
  Ѵ.  absolute Ͼտ Ʈ پ ִٸ,   ȯ
    ̸̶ ϰ, ׷ ʰ ٸ ڰ پ ִٸ,
  밳   origin ̶ Ѵ.  origin  տ @
  δ.

   Ͽ ִ  ʹ resource records Ǵ ٿ RR
   ִ.  ̰͵ DNS ؼ   ִ   
      ִ.  ڿ ڵ  ¸  ִ.
  ̸׸, ϳ ڵ IP address ȣƮ Ӱ ų
  ǰ, CNAME ڵ   ȣƮ  ִ ȣƮ 
  ͸ Ǿ ִ.  , 115 ִ ׸ 6.3 ,
  virtual brewery شϴ   named.hosts   ִ.

   Ͽ ִ ڿ ڵ带  Ϲ  Ҵϱ ؼ
     .

       [domain] [tt1] [class] type rdata

   ʵ   еǾ ִ.   ù °    
   ȣ , ݴ ȣ  ʵ忡 شѴٸ, ϳ
  ü     ̾ ִ. ݷа ο λ̿
  ִ  õȴ.

     domain
        ̰  ü  ӿ Ű ̴.  ƹ
        ε ־ ʾҴٸ, RR   Ų
        RR̶ Ѵ.

     ttl
        Ư ð Ŀ resolver    Ű
        ϱ ؼ  RR "time to live" ٿ ttl Ѿ Ѵ.
        ttlʵ  κ ˻ Ŀ ȿϰ   
        ð Ѵ.  ð 10  ǥϸ 밳  
        ƶ ڷ Ǿ ִ.  ƹ ttl ־
        ʾҴٸ,  SOA ڵ  minimun ʵ带 ʱⰪ
        Ѵ.

     class
        ̰ IP ּҸ  IN Ǵ Hesiod Ŭ ִ ü 
        HS   ּ Ŭ̴. TCP/IP Ʈŷ,  
        IN  Ѵ. ƹ class ʵ嵵 ־ ʾҴٸ,
        ̰  RR Ŭ Ѵ.

     type
        ̰ RR ¸ Ѵ. Ϲ ´ A, SOA, PTR ׸
        NS̴.     RR ¸ ش.

     rdata
        ̰ RR õǾ ִ ͸ ξ   Ѵ. 
        ʵ   RR ¿ Ѵ.   RR 
          ִ.  DNS  Ͽ Ǵ RR ϵ
        δ   ʾҴ. ⼭    RR ϵ
           ִ. ⿡ Ϲ  ϴ  
        Ҵ.

     SOA
        ̰   ǥ  ְ ִ. (SOA "Start of
        Authority" ǹ .)  ȣ SOA RR شϴ  ڵ尡
              ִٴ   ǥ ش.
        primary  忡 ԵǾ ִ     ̷ 
          SOA ڵ带 ԽѾ Ѵ. ⿡  ִ  
        ʹ   ʵ带 ϰ ִ:

        origin
           ̰    ̸Ӹ   ȣƮ
           Ų.  ̰ 밳  ̸ ־.

        contact
           ̰   ϰ ִ  ڿ ּҸ
           Ų.  ̰  Ʈ ſ  '@'̶ ڸ Ѵ.
           ̸׸, Virtual Brewery ϰ ִ  janet̶
           . ׷    ּҴ  janet.vbrew.com
            .

        serial
           ̰ (zone)   ȣ Ų. ̷ ȣ
            ϳ ǥõǾ ִ.  Ͽ Ͱ  
           ,  ȣ ϳ Ѵ.   ° Ӽ 
           Ǵ  ø ȣ (zone)  Ǿٴ 
           νĽ ش. ׷ Ͱ ְ    °
           Ӽ   ΰ  ̸Ӹ  SOA
           ڵ带 ûϰ,  SOA ڵ带 ø ȣ
           Ѵ.   ȣ Ǿٸ,  ° 
           ̸Ӹκ  (zone) ͺ̽
           ۹޴´.

        refresh
           ̰  °  ̸Ӹ  SOA ڵ带 ˻ϴ
           ȿ ٸ ð Ÿش. ̰͵ κ 10
           Ǿ  8 ƶ ڷ Ÿ. Ϲ,
           Ʈũ (topology) ״    ʴ´.
           ׷, Ŵ Ʈũ ̺   Ʈũ
           Ϸ  ΰ  ־  .

        retry
            ȣ  °  ̸Ӹ   ϴ ð
              .    ȣ ũ ´ٸ, Ͻ
            г Ʈũ     °   Ʈũ
           ڿ Һϴ  ʷ  ִ. ѽð ̳ ݽð
            ˸´.

        expire
           ̰  °   ̻ ̸Ӹ   
            ° Ǿ ,    
           (zone)͸  ó  ɸ ð Ÿش.
           Ϲ ſ ũ  ̴. Craig Hunt ([Hunt92])
           42 ǹѴ.

        minimum
           ̰ ڿ(resource) ڵ带  ttl ʱⰪ
           Ÿָ, ̰ ϰ   .  ̰ Ư
           ð    RR(ڿ ڵ)  óϱ  
           ٸ   ʿϴ. ׷   ð 帣,
            °     ʴ´.  밳 LAN
           Ʈũ    ʱ  minimum  ũ
           ƾ  Ѵ.   Ǵ     ùٸ ̴.
           ϳ RR   Ǵ 쿡,  װ͵ ٸ
           ttl Ҵ  ִ.

     A  ̰ ȣƮ  ִ IP ּҿ õǾ ִ.
        ڿ(resource)  ʵ dotted quad notation ǥǾ
        ִ ּҸ  ִ.   ȣƮ  ϳ A ڵ尡
        ҴǾ Ѵ.  A ڵ忡 Ǵ ȣƮ 
        ȣƮ  Ѵ. ٸ  ȣƮӵ CNAME
        ڵ带   ȣƮӰ Ǿ Ѵ.

     NS ̰ (subordinate)      Ų. NS
        ڵ带  ϴ   2.5 Ÿ  ִ.
        ڿ(resource) ʵ  Ӽ ȣƮ 
        ִ.  ȣƮ Ű ؼ ߰ A ڵ尡
        ʿϴ.   glue ڵ ϸ, ̰  Ӽ IP
        ּҿ    ִ.

     CNAME
        ̰ canonical hostname̶ ϴ ȣƮ  õǾ
        ִ.     ϴ A ڵ ߿ ȣƮӵ
        ԵǾ ִ; (alias) ܼ CNAME ڵ忡 Ǿ
        ,   üμ  ƹ ڵ嵵   ʴ.

     PTR
         ڵ ´ ȣƮ   ִ in-addr.arpa 
        ΰ   Ѵ. ̰ IP ּҰ  ϴ
        ȣƮ ų  Ѵ.  ̶ ȣƮ
         ϰ ִ ȣƮ̾ Ѵ.

     MX ̰ RR mail exchanger Ű Ѵ.  ȯ(mail
        exchanger)   13 Mail Routing on the Internet
         ̴. MX ڵ  ȯ⸦ ؼ domain host
         ٲپ ִ  Ѵ.

                         [domain] [ttl] [class] MX preference host

       ȯ װͰ  õǾ ִ ·  Ǿ ִ
     preference  ִ. domain  ϱ ٶ 
      (mail transport agent) ̷ ް   ,
     MX ڵ带  ִ  ȣƮ Ǹ  ̴.
     켱   ͺ Ǹ  ̴.

     HINFO
         ڵ ý  ϵ Ʈ  
        Ѵ.  ̰   .

                         [domain] [ttl] [class] HINFO hardware software

     hardware  ȣƮ  Ǵ ϵ   ִ
     ʵ̴. ̰   ֱ ؼ ϴ Ư ȯ۾
     ִ. ⼭ ϴ ̸  "Assigned Numbers" (RFC 1340)
     ־ ִ.  ϳ ʵ忡   ַ Ѵٸ,  ʵ带
     "  Ѵ. software ʵ ýۿ  Ǵ ü
     Ʈ Ű ̸̴.  ̸ "Assigned Numbers" RFC
     ԵǾ ִ.

  6.2.3.  Writing the Master Files

  ׸ 6.2, 6.3, 6.4 ׸ 6.5 brewery  vlager Ǿ ִ
  Ӽ  ̴. ⼭  ϵ ü 
  ͵̴.       ٸ, named   ,
  Cricket Liu   Paul  Albitz([AlbitzLiu92])  "DNS  and BIND"
  ϶.

  ׸ 6.2 ̴ named.ca (cache)  Ʈ Ӽ 
  ڵ带  ִ ϴ  ִ ̴.   
  밳 12 Ӽ    ´.     Ǿ
  ִ nslookup  ؼ,   Ʈ   
  Ӽ    ִ.

       ; /var/named/named.ca         Cache file for the brewery
       ;                  We're not on the Internet, so we don't need
       ;                  any root servers. To activate these
       ;                  records, remove the semicolons.
       ;
       ; .                   99999999   IN   NS   NS.NIC.DDN.MIL
       ; NS.NIC.DDN.MIL      99999999   IN   A    26.3.0.103
       ; .                   99999999   IN   NS   NS.NASA.GOV
       ; NS.NASA.GOV         99999999   IN   A    128.102.16.10

                        ׸ 6.2: named.ca 

  6.2.4.  Verifying the Name Server Setup

      ˻ϱ  ϴ    ִ.
  nslookup ϴ ̰ ȭγ ࿡   ִ.
  ϰ     ְ,

       nslookup hostname

  ̰ resolv.conf õǾ   hostname شϴ
  Ӽ  ̴.  ( ȿ ϳ ̻  ִٸ,
  nslookup Ƿ ϳ  ̴.)

   ȣƮ ϴ ȭ 忡 DNS ڵ¸ ϰ,
  ش   ü   Ѵ.

  ƹ μ nslookup ϸ,   Ӽ ȭ鿡
  ϰ, ȭ    ̴. > Ʈ, 
  ؾ   Է   .

  ⺻ Ŭ A ڵ带 ûѴ.  ڵ  Ӱ
  Ǿ ִ IP ּҸ ϰ ִ.

   "set type=type" Էν  ̷ ¸ ų  
  ִ. type 6.2 Ǿ ִ ڿ ڵ ̸ ϳ ȴ.

   ,    ȭ(dialogue)   ִ:

       $ nslookup
       Default Name Server:  rs10.hrz.th-darmstadt.de
       Address:  130.83.56.60

       > sunsite.unc.edu
       Name Server:  rs10.hrz.th-darmstadt.de
       Address:  130.83.56.60

       Non-authoritative answer:
       Name:  sunsite.unc.edu
       Address:  152.2.22.81

     IP ּҵ    ȣƮ ãų, DNS
  ͺ  Ǵٸ ڵ带 ã ϴ , nslookup  "No
  type A records found"   ȭ鿡  ̴. 
   "set type" ɿ A  Էؼ  带  Ǹ
    ִ.  , unc.edu SOA ڵ带  ؼ,  
   ϶:

       > unc.edu
       *** No address (A) records available for unc.edu
       Name Server:  rs10.hrz.th-darmstadt.de
       Address:  130.83.56.60

       > set type=SOA
       > unc.edu
       Name Server:  rs10.hrz.th-darmstadt.de
       Address:  130.83.56.60

       Non-authoritative answer:
       unc.edu
               origin = ns.unc.edu
               mail addr = shava.ns.unc.edu
               serial = 930408
               refresh = 28800 (8 hours)
               retry   = 3600 (1 hour)
               expire  = 1209600 (14 days)
               minimum ttl = 86400 (1 day)
       Authoritative answers can be found from:
       UNC.EDU nameserver = SAMBA.ACS.UNC.EDU
       SAMBA.ACS.UNC.EDU      internet address = 128.109.157.30

    MX ڵ带 ϰ Ǹ, ־ ̸ Ǿ ִ
      ڵ带 ǵ ְ ȴ.

       > set type=MX
       > unc.edu
       Non-authoritative answer:
       unc.edu preference = 10, mail exchanger = lambada.oit.unc.edu
       lambada.oit.unc.edu      internet address = 152.2.22.80

       Authoritative answers can be found from:
       UNC.EDU nameserver = SAMBA.ACS.UNC.EDU
       SAMBA.ACS.UNC.EDU       internet address = 128.109.157.30

   ִ nslookup ø̼ named.ca Ͽ 
  ϰ ִ  ƮӼ  ش.

       > set type=NS
       > .
       Name Server:  fb0430.mathematik.th-darmstadt.de
       Address:  130.83.2.30

       Non-authoritative answer:
       (root) nameserver = NS.INTERNIC.NET
       (root) nameserver = AOS.ARL.ARMY.MIL
       (root) nameserver = C.NYSER.NET
       (root) nameserver = TERP.UMD.EDU
       (root) nameserver = NS.NASA.GOV
       (root) nameserver = NIC.NORDU.NET
       (root) nameserver = NS.NIC.DDN.MIL

       Authoritative answers can be found from:
       (root) nameserver = NS.INTERNIC.NET
       (root) nameserver = AOS.ARL.ARMY.MIL
       (root) nameserver = C.NYSER.NET
       (root) nameserver = TERP.UMD.EDU
       (root) nameserver = NS.NASA.GOV
       (root) nameserver = NIC.NORDU.NET
       (root) nameserver = NS.NIC.DDN.MIL
       NS.INTERNIC.NET internet address = 198.41.0.4
       AOS.ARL.ARMY.MIL         internet address = 128.63.4.82
       AOS.ARL.ARMY.MIL         internet address = 192.5.25.82
       AOS.ARL.ARMY.MIL         internet address = 26.3.0.29
       C.NYSER.NET      internet address = 192.33.4.12
       TERP.UMD.EDU     internet address = 128.8.10.90
       NS.NASA.GOV      internet address = 128.102.16.10
       NS.NASA.GOV      internet address = 192.52.195.10
       NS.NASA.GOV      internet address = 45.13.10.121
       NIC.NORDU.NET    internet address = 192.36.148.17
       NS.NIC.DDN.MIL    internet address = 192.112.36.4

  nslookup   ִ  ɾ  nslookup ɿ help
  Էν    ִ.

  6.2.5.  Other Useful Tools

   BIND ڷν     ,     ִ 
   ִ.   װ͵ ΰ  ϰڴ.
  װ͵  ϴ  ؼ    
  ϱ ٶ.

  hostcvt  /etc/hosts  named شϴ Ϸ
  ȯŴν, BIND ȯ ʱȭų   ټ ִ  ̴.
  ̰  ߴ A ڵ PTR ڵ带 Ű, (alias)
  ϴ   Ѵ. , ü ۾ ϴ  ƴϴ. ̸׸,
  SOA ڵ忡 ִ Ÿ ƿ  ġѾ Ѵٵ, MX 带
  ߰Ѿ ϴ ۾  е ̴. BIND ҽ Ϻκ
  hostcvt   FTP  ִ ĵ Ű ãµ
    ִ.

   Ӽ ϰ , ȯ   ;ҷ
  𸥴. ̷  ۾ ϱ ؼ  perl ʸ ΰ ִ
  dnswalk  ϶. ̰ DNS ȸϸ鼭, Ϲ 
  ˻ϰ,  ġϴ ϴ  Ѵ.  dnswalk
  comp.source.misc ֱ ǰ ,  ׷( 
   Ʈ  ʾҴٸ, ftp.uu.net  δ ͵  
   ̴.) ִ  ϰ ִ  FTP Ʈ 
    ִ.

  7.  Serial Line IP

  ø   SLIP PPP ͳݿ   ϴ
  ̴. 𵩰   FIFO  ġ ߰  ִ ø
  忡  ϵ  ʿ  .  ø 带 ϴ
    ϴ ͺ  ϱ ,  ݴ
  ̾ IP ϴ 缳 ü ϰ ִ.

   ϰ   ִ  SLIP PPP 尡 ִ.  SLIP
     Ǿ, PPP ֱٿ Michael Callahan Al
  Longyear ؼ ߵǰ ִ.   κп ؼ 忡
  ڼϰ  ̴.

  7.1.  General Requirements

  SLIP PPP ϱ ؼ    忡 ߴ  ⺻
  Ʈŷ ȯ  ƾ Ѵ. ,  ַ 
  ִ  ̽     ƾ Ѵ. ͳݿ 
  , ¼ DNS ϰ  ̴.    δ 
   ּҸ resolv.conf Ͽ ־ δ ̴. SLIP  Ȱȭ
   ڸ   Ȱȭ ų ̴. ׸    
    δ ͵  ̴.

  ׷,   ּ ͸ ƴϴ. ֳϸ,   
  SLIP/PPP ũ  ؼ ̷ ̴.  뿪 Һϴ 
  ȴٸ, caching-only       ִ.  
    ʴ´ٸ, ̷ ũ   ȣ Ʈ Ǵ
  DNS ǿ  ä Ȱ  ̴.    ִٸ, 
   ĳø   ִٴ ̰, ׷ν κ Ǵ 
  ѹ ø  ļ  ȴ. caching-only   ִ
  named.boot     ¸  ִ.

   ; named.boot file for caching-only server
   directory                            /var/named
   primary     0.0.127.in-addr.arpa   db.127.0.0 ; loopback net
   cache       .                      db.cache  ; root servers

  Դٰ named.boot Ͽ Ʈ   ȿ   ִ
  db.cache    ξ Ѵ.

  7.2.  SLIP Operation

  ȭӿ  IP-server  Ư ڰ Ͽ SLIP
  񽺸 Ѵ. ׷   Ŀ  Ϲ shell
   ʴ´ ;  α׷̳ Ȥ shell script  
  serial line  SLIP driver Ű ǰ  Ʈũ
  ̽ ϰ ȴ.

   ü, SLIP driver   α׷̴; Ŀ
  Ϻκ 쿡 ӵ  . ׷ ̰ serial line SLIP
   ȯ  䱸Ѵ. ̰ SLIPDISC Ư tty line
  discipline  ̷. tty normal line discipline(DISCO)ε
  Ͽ ̰  user processes data ȯϸ  б(2)
  (2) ȣ ϰ, SLIP driver tty Ͽ аų  
  . ݸ鿡  serial port Ͽ   data SLIP driver
   Ѵ. SLIPDISC   ڹٲ ȴ:   
   process tty  ų д  ܵǰ, ׵
  serial port    data SLIP driver 
  ޵ȴ.

  SLIP driver  ü SLIP    ȭ Ѵ.
   SLIP , װ IP-packet    Van
  Jacobson header compression  ϴ CSLIP  Ѵ. ̰
  interactive session  throughput ϰ ߴ޽Ų.
  ߰ ̵ ݵ  6-bit  ִ.

  Serial line SLIP  ȯϱ    slattach tool
  ̿ ̴.   /dev/cua3 ִٰ ϰ, SLIP server
   Ͽٰ . ׷  ̷ Ѵ.

          # slattach /dev/cua3 &

  ̰ cua3 line discipline SLIPDISC ȯϰ, װ SLIP
  network interface  ϳ ̰ ȴ.  ̰  ù°
  active SLIP link line sl0 ٰ ȴ; ι° sl1 ٰԵ
  ̰  ̷  .  Ŀ ÿ 8 SLIP
  link Ѵ.

  Slattach  ⺻ õǴ encapsulation CSLIP̴. 
  -p ġ  ٸ 带   ִ. Ϲ SLIP(
  ʴ) ϱ ؼ      ִ.

          # slattach -p slip /dev/cua3 &

  Ǵٸ  cslip, slip6, cslip6(SLIP 6-bit version ),
  ׸ adaptive SLIP  adaptive ִ. ڴ Ŀ 
  ڵ SLIP encapsulation  ãƳ д.

    peer ϴ Ͱ  encapsulaiton ؾ Ѵٴ
   Ͽ Ѵ.  ,  cowslip CSLIP Ѵٸ
  ŵ  װ ؾ Ѵ. Mismatch   ȣƮ
  ping Ͽ  packet ٽ  ʴ´.  ٸ
  ȣƮ ſ ping Ͽ  ֿܼ "Can't build ICMP
  header" ޼ Եȴ. ̷  ذϴ   ϳ
  adaptive SLIP ϴ ̴.

  , slattach  SLIP ϰ ִ  ƴ϶, PPP
  KISS(ham radioڵ  Ǵٸ )  serial line
   ٸ  뵵 ϰ ش.  ڼ  ؼ
  slattach(8) Ŵ  ϶.

  SLIP driver ȯ Ŀ,  network interface  ־
  Ѵ. ٽ 츮 ǥ Ǵ ifconfig route  Ѵ.
  vlager   츦 ؼ 츮 cowslip̶ 
  dial up ߴٰ .  ̷ ؾ Ѵ.

          # ifconfig sl0 vlager pointopoint cowslip
          # route add cowslip
          # route add default gw cowslip

  ù°  interface point-to-point link cowslip
  Ѵ. ι° °  cowslip route ϴ
  ̰, default route cowslip gateway ڴٴ ̴.

  SLIP link  ,   cowslip   route del
  option ؾ Ѵ. interface ϰ slattach 
  ڴٴ ȣ  Ѵ.   ٽ  ͹̳ α׷
  ̿Ͽ   Ѵ.

          # route del default
          # route del cowslip
          # ifconfig slo down
          # kill -HUP 516

  7.3.  Using dip

     ټ Ͽ. ׷ ұϰ  
      ܼ ɸ ڵ ϱ⸦
   𸥴. dip ٷ ̰  ̴.   
    3.3.7̴. ̰  鿡  heavilyϰ
  ġǾǷ  '' dip α׷ ؼ  ̻  ʿ䰡
  . ̷  ٸ  ̷  hopefullyϰ merged
  in ɰ̴.

  dip   ϰ,line SLIP  ȯϰ, interface
  ϱ   scripting     ִ. ̰ ټ
  ̰ ̱  κ 쿡 ϴ.  ο
  release dip   versatile   ̴.

  SLIP interface ϱ ؼ, dip root  䱸Ѵ. װ
  dip setuid root   Ȥϴ  ׷  ڵ 
  SLIP  root  ̵   ְ ȴ. ̰ ſ
  ѵ, ֳϸ bogus interfaces ϴ Ͱ dip ̿
  default route  network ɰϰ ջų ֱ ̴.
    ,  ڵ鿡 '' SLIP    ִ
   ְ Ǵ ̸  Ʈũ     ְ
  ȴ. ׷   ڵ鿡 SLIP  ϵ ϰ
  ʹٸ,   SLIP    wrapper α׷
  ϰ,  wrapper    Ư script
  invokeϰ ȴ.  α׷ ϰ root    ִ.

  7.3.1.  A Sample Script

      Figure: A sample dip script

              # cow slip ȭ  dip  ũƮ
              # ð  ̸ ּҸ 
              get $local vlager
              get $remote cowslip

              port cua3                # ø Ʈ 
              speed 38400              # ִ ӵ 
              modem HAYES              #   
              reset                    # 𵩰 tty 缳
              flush                    # flush out modem response

              # ȭɱ⸦ غ
              send ATQ0V1E1X1\r
              wait OK 2
              if $errlvl != 0 goto error
              dial 0123456789
              if $errlvl != 0 goto error
              wait CONNECT 60
              if $errlvl != 0 goto error

              # ,  !
              sleep 3
              send \r\n\r\n
              wait ogin: 10
              if $errlvl != 0 goto error
              send Cvlager\r
              wait ssword: 5
              if $errlvl != 0 goto error
                  #better not leave your password in ascii (thanx noud)
              password
              wait running 30
              if $errlvl != 0 goto error
          #  IP ϱ 
          get $remote remote
          print remote = $remote
          if $errlvl != 0 goto error
          wait to 3
          get $local remote
          print local = $local
          if $errlvl != 0 goto error

          #  츮 Ǿ,  CSLIP 
          print Connected to $remote with address $rmtip
          default                  # Make this link our default route
          mode CSLIP                # We go to CSLIP mode, too
          #   
          error:
          print CSLIP to $remote failed.

   ũƮ   . Argument  ũƮ
  ̿ dip cowslip ϱ   ̴.

             # dip cowslip.dip
             DIP: Dialup IP Protocol Driver version 3.3.7 (12/13/93)
             Written by Fred N. van Kempen, MicroWalt Corporation.

             connected to cowslip.moo.com with addr 193.174.7.129
             #

  Cowslip ϰ, CSLIP ϰ  Ŀ dip ͹̳ 
  ׶ ۾ ȯ ̴. ׷ Ŀ  CSLIP ũ
  ̿Ͽ Ϲ Ʈŷ 񽺵 ̿  ִ.   
  Ͽ, ܼ -kɼ ϸ ȴ. ̰ ȭ  ȣ
  /etc/dip.pid ִ dip pid ˾Ƴ dip .

             # kill -k

  dip ũƮ , $ ǥð տ ٴ Ű  ̸
  ǥѴ.dip Ʒ  ̸ ǵǾ   
  ִ. SLIP ũ  local remote ȣƮ ϰ ִ
  $remote $local   ̴.

   ũƮ ִ ó   dip  ϴ ɵ
    ̴. ⿡ local remote ȣƮ  
  vlager cowslip Ǿ.

   ټ  ͹̳ ΰ  Ѵ.  reset reset
  ڿ  . ; Hayes ȣȯ  , ̰ ATZ
  ̴.     Ų. ׸Ͽ α chat
      ۵  ֵ ִ ̴.  chat 
   θ ư: ̰ ܼ cowslip ȭȣ 49188
  ȭ ɰ, hey-jude ȣ ̿Ͽ Svlager  αѴ.
  wait dip ù° argument  ٸ Ѵ.; ι°
  argument ־ ڴ   ڿ ŵ ʾ 
  ־  ðŭ ϵ ϴ ̴. if   Ǵ
     ߻   α  Ѹ(?).

    default α  Ŀ ȴ.   ο SLIP
  带 ϰ ְ, ſ ´ ̽  ̺
  ִ default route  ȣƮ  SLIP ũ
  ش.

  7.3.2.  A dip Reference

  ſ θ ӿ ұϰ, dip      ʾҴ.
   κп  κ dip ɾ   ̴.  
  dip ׽Ʈ 忡  ɾ Ⱦ  ְ help 
  ̿ؼ      ִ. ɵ  κе
  ˾ƺ     װ Էؾ Ѵ. ;  
  ̴  ۵  ʴ´.

             DIP> help
             DIP knows about the following commands:

                     databits default  dial     echo     flush
                     get      goto     help     if       init
                     mode     modem    parity   print    port
                     reset    send     sleep    speed    stopbits
                     term     wait

             DIP> echo
             Usage: echo on|off
             DIP>

  Ʒ,  DIP> Ʈ  ׽Ʈ 忡 Էϴ
  ְ,    Ÿ ش.

  7.3.2.1.  The Modem Commands

   ø ΰ  ϱ  dip ϴ  ſ
  . ̵  ø Ʈ, ӵ ŸƮ, Ʈ, зƼ
  ϴ port  Ϲ   ϴ ɵ 
  ϴ.

  modem    Ѵ.  Ǵ Ÿ
  HAYES(빮ڰ 䱸)ۿ .  ݵ dip  Ÿ
  ־ ϸ, ׷   ̾ reset źε
  ̴. reset  reset ڿ 𵩿 .; ű⿡ ̴
  ڿ õ   . Ϲ Hayesȣȯ 
  쿡 ATZ ȴ.

  flushڵ  ָ  ɵ Űµ ȴ(?). ׷
   reset ɵڿ  chat ũƮ ȥ Ǵµ
  ̰  OK  п Ǳ ̴.

  init   ȭ ɱ ʱȭ  Ѵ. Hayesȣȯ
    ⺻ ``ATE0 Q0 V1 X1''̴.

  dial   ʱȭ ڿ  Ŀ  ýۿ ȭ
  Ǵ. Hayes   ⺻ ATD̴.

  7.3.2.2.  echo and term

  echo     ȴ. echo on ϰ Ǹ ø
      ֿܼ dip echoϰ ȴ. ̰ echo off
   .

  dip   Ͻ ũƮ 带  ͹̳ 
    ش.  忡  dip Ϲ ͹̳
  α׷ó   , ø ο , װκ 
   ִ.  带 ϱ ؼ Ctrl-] Է϶.

  7.3.2.3.  The get Command

  get  dip  ϴ ̴.    
      ϴ ̴. ׷ Ƹ 
  ڿ   ſ  Ư Ű带 Էϵ ϰ 
  ̴.

             DIP> get $local ask
             Enter the value for $local:

  °  ȣƮκ   ̴. ó 
  Bizarre   쿡 ̰ ſ ϴ:  SLIP 
  SLIP ũ Ÿ IP-ּҸ  ʰ, ſ  ּҰ
  ҴǾ ִ  ޼  ָ鼭  ּҸ 
  𿡼 ϵ ſ Ҵ ̴.   ޼ "Your
  address:193.174.7.202" ̷  δٸ Ʒ dip code 
  ϴ ּҸ   ֵ   ̴.

          wait address: 10
          get $locip remote

  7.3.2.4.  The print command

  ̰ dip ۵ ֿܼ ؽƮ echoϱ  ̴. 
    dip  print ɿ   ִ.

             DIP> print Using port $port at speed $speed
             Using port cua3 at speed 38400

  7.3.2.5.  Variable Name

  dip   ǵǾ ִ 鸸 Ѵ.  ݵ $
  ؾ ϸ ҹڵ  Ѵ.

  $local $locip   ȣƮ ̸ IP-ּҸ Ѵ.
  ȣƮ ϴ  dip  ȣƮ $local
  ϸ, ÿ ׿ شϴ IP-ּҸ $locip Ѵ. 
  찡 $locip  쿡 Ͼ.

  $remote $remotip 鵵 Ȱ ȣƮ ̸ ּҸ
  Ѵ. $mtu  MTU  Ѵ.

  ̵ ټ  get  ̿  Ǵ ̴.
  ٸ  host  ׿ شϴ ɵ鸸 ̿ ǳ
  print   ȴ. ; ̷ ͵ $modem, $port, ׸
  $speed̴.

  $errlvl     Ǵ ̴.   
  0̸  ǹϰ ٸ 0 ƴ  쿡  ǹѴ.

  7.3.2.6.  The if and goto command

  if  Ϲ ϴ if⺸ٴ Ȳ  ̴. 
  

             if var op number goto label

   ǥ ݵ $errlvl, $locip, and $rmtip   ̿
   񱳿 Ѵ. ι° ǿڴ ݵ  Ѵ; ڴ
  ==, !=, <, >, <=, ׸ >=  ϳ̾ Ѵ.

  goto   ϰ ִ  ũƮ  
  ϰ Ѵ.  ݵ   ùκ̾ ϸ, ݷ ڿ
  پ Ѵ.

  7.3.2.7.  send, wait and sleep

   ɵ dip  chat ũƮ  ̴. send
  װ argument ø  Ѵ.  
   n b   C-Ÿ  ڽ νѴ.
  ƿ幮 () /๮  Ѵ.

  wait  ܾ ϳ argument ϰ, װ  ܾ ν
   ø    Է ˻Ѵ.  ܾ ڽ 
  ĭ  ־ ȵȴ. ,  ι° argumentν
  timeout ־Ѵ.;  Ǿ ڰ  ð 
    ʴ´ٸ   1̶ $errlvl ȯѴ.

  sleep    Ư ð ϱ  Ѵ.  
  α  Ϻϰ γְ ٸ  ȴ. ٽ, 
  ð ʷ ǥȴ.

  7.3.2.8.  mode and default

   ɵ ø  SLIP ȯϰ ̽ ϱ
   ȴ.

  mode     dip  Ǵ 
  ̴.  ߻ ʴ´ٸ   ȯ ʴ´.

  mode  ̸ argument Ѵ.  dip SLIP
  CSLIP ȿ ̸ νѴ. ׷   dip adaptive
  SLIP ν Ѵ.

  ø ο SLIP 带 ϰ  Ŀ, dip ̽
  point-to-point link ϱ   ifconfig ϰ ǰ θ
   ȣƮ ߱  route õѴ.

  ߰, ࿡ ũƮ   ⺻  Ѵٸ, dip ⺻
  route point SLIP ũ  ̴.

  7.4.  Running in Server Mode

   SLIP Ŭ̾Ʈ ϴ  ô  ̴. ׷ ̿
  ,   ȣƮ SLIP   ξ  ̴.

  ̰ ϰ ϴ   ϳ diplogin  dip 
  ϴ ̴. ̰ ֿ ȭ  ȣƮ ִ α
  ̸ ּҰ ִ /etc/diphosts ȭ̴.  
  BSD   sliplogin   ִ. sliplogin 
  ؾ ϴ ȣƮ Ӱ    ũƮ   ϰ
    ִ.  ̰ Ÿ̴.

   α׷  ϳ SLIP Ŭ̾Ʈ  ϳ α 
  䱸Ѵ.    dent.beta.com Arthur Dent SLIP 
  ڰ ȴٰ غ.  ȣƮ passwd ȭϿ 
    ߰ν dent   Ѵ.

             dent:*:501:60:Arthur Dent's SLIP account:/tmp:/usr/sbin/diplogin

  ׷ Ŀ  dent йȣ passwd utility ؼ ؾ
  Ѵ.

   dent α ϰ, dip   ̴. װ 
  SLIP ϵ 㰡 Ǿ ˾ƺ  dip /etc/diphosts
   ̸ ã ̴.  ȭ  SLIP ڵ 㰡
  Ǹ  Ķͷ   ̴. dent   Ƹ
    ̴.

  dent::dent.beta.com:Arthur Dent:SLIP,296

  ù° ݷ  κ α  ̸ ̴.
  ι° κ йȣ ϰ  ̴(Ʒ ). °
  κ Ŵ  ȣƮ̰ų IP-̴ּ.   
  ״  ǹ̰  ͵̴.  κ  Ķ͵̴.
  ̰ ޸ иǾ MTU ھ ٴ (μ SLIP̳
  CSLIP) Ѵ.

  dent α , diplogin diphosts ȭϷκ ׿  
  ϰ , ι° κ  ʴٸ "ܺ  йȣ"
  䱸Ѵ. ڿ  Էµ  ڿ diphostsȭ
  password(ȣȭ ) 񱳵ȴ.     ʴٸ
  α õ źεȴ.

  ׷ ʰ diplogin ø CSLIP̳ SLIP  
  , ̽ route Ѵ.   ڰ 
  ų  ȭ 涧 ִ. ׷ diplogin 
  Ϲ   ´.

  diplogin super-user  䱸Ѵ.   dip root 
     ܼ ũ ſ  diplogin и dip
  纻  Ѵ. ׷ diplogin dip  ڽ ¿
   ġ ʰ  setuid  ְ ȴ.

  8.  The Point-to-Point Protocol

  8.1.  Untangling the P's

  SLIP , PPP ø   Ÿ 
     Ѵ. װ Ҷ ִ
  datagram ũ IP ּҿ  ͵   ֵ ָ
  Ŭ̾Ʈ Ȯ ش. ̷  ɷ¶, PPP 
   . Ʒ 츮 ϰ ̿   PPP
  ϵ ˾ƺ ̴. ̰  Ϻ ʴ. ;  
  PPP   ˰ Ѵٸ  RFC-1548 ִ  о
  ϸ  RFC    оƾ  ̴.

  PPP   κ 16-bit checksum  PP ӵ 踦
  ϴ High-Level Data Link Control ̴.   
  SLIP encapsylation ݴ, PPP  IP ƴ Novell IPX
  Appletalk  ݵ Ŷ Ƶ  ִ. ̴ PPP
  ӿ  ޵Ǵ Ŷ  Ȯϴ ⺻ HDLC ӿ
    ߰ν ̷.  LCP, Link Control
  Protocol, ʿ ޾Ƶϼ ִ ִ Ÿ ũ datagram
  ũ⸦ ִ Maximum Receive Unit(MRU)  Ÿũ ִ
  ſɼ  HDLC  κп ȴ.

  PPP ũ  ߿ ܰ Ŭ̾Ʈ 㰡̴. 
  װ ӵ ̱ ƴϱ  ̾ ε鿡 ݵ
  ʿϴ.  Ϲ ȣƮ Ҹ ʿ  Ư ȣ
  ƴ° ؼ Ŭ̾Ʈ ڽ ϵ ´.  ȭ 
   Ȯ ȣ µ ϸ  . PPP 
    ̴ ; , ȭ      ڽ ϵ
  Ѵ.   μο  ϴ. ⿡ ΰ 
  ٸ   ִµ,   ڼϰ ٷ ̴. ̰͵
  Password Authentication Protocol, Ȥ PAP, ׸ Challenge Handshake
  Authentication Protocol, Ȥ CHAP ̸ ٿ ִ.

  IP AppleTalk   Ÿ ũ ġ  Ʈũ
  ݵ Network Control Protocol(NCP) Ͽ 
  ȴ.   ũ  IP datagram  , PPP IP-
  datagram Van-jacobson   Ѵ. ̰ TCPŶ
   3Ʈ  ۰ ϱ  ̴. ̰ CSLIP
   Ǹ    VJ-࿡ ޵  ִ. 
   IPCP  start up    ̷.

  8.2.  PPP On

  PPP  ũ  κ . ù° Ŀ  ġϴ 
   HDLC driver̰, ι°  control protocol ϴ
  ڿ pppd deamon̴.  release PPP linux-ppp-1.0.0̸
  Ŀ PPP , pppd,  ýۿ ȭ Ŵµ ̴ chat̶
  α׷ ϰ ִ.

  PPP Ŀ ̹ Michael Callanhan  . pppd Drew
  Perkins ٸ 鿡   SUN 386BSD  ο PPP
  implementation derived  Paul Mackerras  ǰ ִ.
  ̰ Al Longyear  õǾ.  SLIP , PPP Ư line
  discipline  implementedǾ.  serial line PPP link
   ؼ,   Ϲ    
  ؾ ϸ,   line PPP mode ٲپ Ѵ.  忡,
    data  validity( HDLC frame 16-bit
  checksum Ѵ)  HDLC frames ˻ϰ, װ ٽ Ǯ
  diapatcheϴ  PPP ̹ ľ Ѵ. , װ IP
  datagram   ְ,  Van-Jacobson header
  compression   ִ. IPX  , PPP ̹ IPX
  Ŷ    ̴.

  Ŀ ̹ ũ   Ʈũ Ʈ  ʿ
  ü ʱȭ authentication phase ϴ PPP daemon, pppd
   aidȴ. pppd ൿ    ɼǵ ϴ Ͱ 
  ̴. PPP ټ ϱ , װ ϳ 忡  ͵
  ϴ  Ұϴ.  å pppd  ͵   
  ̴. ׷  ſ Ұϴ     ̴. 
    ؼ Ŵ  pppd ҽǿ ִ README
  ϶. ׷  忡  ǵ ߱   ñ 
   ִ ׿ ؼ     ̴.   
    о ȴٸ, pppd  õ  
  ִ ׷ comp.protocols.ppp ϶.

  8.3.  Running pppd

   PPP link  ͳݿ ϰ ʹٸ, loopback device
  resolve  ͵ ̿ؼ ⺻ Ʈŷ capabillity
  ¾ؾ Ѵ. ʴ 忡 Ǿ. Serial link ̿
  DNS 뿡 ؼ ̾߱Ͽ  ͵ ִ. ; ̰Ϳ ؼ
  SLIP  ǵ  ϶.  pppd ̿ PPP ӿ 
      ٽ  vlager ִٰ .  ̹
  PPP  c3op ߰ ppp  αϿ. c3po  װ
  PPP ̹ Ͽ. ̾  α׷  
      ؾ Ѵ.

   # pppd /dev/cua3 38400 crtscts defaultroute

  ̰ serial line cua3 PPP flipϰ c3po IP-link
  . Serial port  ۼӵ 38400bps  ̴. Crtscts
  ɼ 9600bps ̻ ӵ Ȯ port ϵ handshake
  Ҵ.  Pppd   ù° ϴ  LCP ϴ  
   link Ư ϴ ̴. Ϲ, ⺻ ɼ
    ϹǷ ⼭   ʴ´.  ǿ 
   ڼ LCP ư ̴.   pppd IP control protocol
  IPCP ϴ IP parameter  ̴.  pppd Ư
  IP-ּҸ  ʾұ , װ resolver Ͽ local
  hostname  ּҸ Ϸ  ̴. ʴ ׵ ּҸ
  ο ˷ ̴.

  Ϲ ̷ ⺻ ؼ ߸  .  
  ǻͿ ̴ݿ ִϴ ̴ݰ PPP interface ο 
  IP-ּҸ   ִ. ׷ ұϰ pppd ſ ٸ
  ּҸ ϵ ϰų, ٸ ּҸ   ´.
  ̷ ɼǵ  忡 ǵ ̴.

  IPCP ¾  Ŀ, pppd  Ʈŷ PPP ũ
  ϱ  غ ̴. ù° PPP Ʈũ ̽ point-
  to-point ũ ϰ, ppp0 ù° PPP ũ, ppp1  °,
  ̷   .  ũ ٸ    ȣƮ
  Ű routing table entry ¾ ̴.   
  pppd c3po ⺻ Ʈũ Ʈ Ʈ  ̴. ֳϸ
  װ defaultroute ɼ ־ ̴. ̰  local
  network  ʴ ȣƮ   datagram c3po 
  Ѵ. Ǵٸ  routing scheme pppd ϸ, װ 
  忡 ڼϰ  ̴.

  8.4.  Using Options Files

  pppd command line argument ϱ, pppd ⺻ ɼ
  Ǿ ִ  ȭϵ ãƺ.  ȭϵ  Ȯ  command
  line argument ϰ ְ,     ɷ   .
  ҰǴ comment Ư ȣ  ִ.  ù° ɼ 
  pppd    ã /etc/ppp/options̴.  ȭ ſ
   ڵ ȿ  Ÿ ϵ ֱ   ȭϿ
   ⺻  ߾   .  , pppd peer
     (PAP CHAP) ϵ ϱ   ȭϿ auth
   ɼ ߰  ִ.  ɼ ڵ鿡  
  ʱ  database鿡 Ǿ    system PPP
  ϴ  Ұϴ.  /etc/ppp/options   Ŀ ã ٸ
  ɼ ȭ  Ȩ丮 ִ .ppprcȭ̴. װ 
  ڵ鿡 ׵鸸 ⺻ɼǵ   ֵ ش.
  /etc/ppp/options ȭ   ϰ̴:

           # Global options for pppd running on vlager.vbrew.com
           auth   #  䱸
           usehostname  # CHAP  local hostname 
           lock   # UUCP-style ̽ ױ  
           domain.vbrew.com # 츮  

  ̵ ɼ ù° ִ ΰ ɼǵ   Ǹ
  Ʒ Ǿ. lock Ű pppd device ״ ǥ UUCP
   ϵ Ѵ. ̰Ϳ   serial device ̿ϴ
  μ, /dev/cua3 , LCK..cua3  lock  device
   UUCP spool directory Ѵ. ̰ minicom̳ uucico
   ٸ α׷ PPP Ǵ  serial device ϴ
   ϴµ ʿϴ.  ̷ ɼǵ ü  ȭϿ 
     Ͱ  ɼǵ ٽ   
  ̰, ׷      ִ. ׷ 
   ӿ  ڿ   ɼǵ ߿ ٽ 
   ִٴ Ϳ ָ϶.
  8.5.  Dialing out with chat

      ϰ  𸣴   ϳ
   pppd ϱ    ؾ ٴ ̴. dipʹ
  ٸ, pppd  ýۿ ȭ ɰ ϴ pppd ڽ
  ũƮ   ʴ. ׷   ϱ  pppd ܺ
  α׷̳ shell ũƮ Ѵ.   Ǿ 
   command line ɼ pppd ־  ִ. pppd  ǥ
  Է°  ø  . ̸   α׷δ
  Don Libes   expect ִ. expect ٷ ̷ 
  α׷  ȵ ſ   Tcl  ΰ ִ.
  Pppd Ű ſ UUCP Ÿ chat ũƮ   ְ
  ִ chat  α׷ Բ ´. ⺻, chat
  ũƮ  ýۿ ƿ ڿ 츮 ׿ ؾ ϴ
  ڿ Ǵ   Ǿִ. 츮  ̰͵
  expect send ڿ̶ Ѵ.  chatũƮ 
  ̴.

           ogin: b1ff ssword: s3kr3t

  ̰ chat  ýۿ α Ʈ ⸦ ٷȴٰ
  α  b1ff ϴ  ش. 츮  ogin: 
  ٸµ ̷  α Ʈ 빮 L ҹ l
  Ű澲 ʾƵ Ǹ, Ȥ ߸ ƿ 쵵 .  
  ڿ chat н Ʈ ٷȴٰ 츮  
  ڿ̴.  ̰ ⺻ chat ũƮ ϴ ̴.  PPP
   ̾   ũƮ  𵩸 ؾ
  Ѵ.   Hayes command set Ѵٰ ϰ, 
  ȭȣ 318714 .  c3po    
  chat ũƮ   ̴.

           $ chat -v '' ATZ OK ATDT318714 CONNECT '' ogin: ppp word: GaGariN

  ǿ , ó ڿ expect ڿ Ǿ   
  츮 װ kick(?)ϱ  ƹ 䵵  ̹Ƿ
  츮 ó  ڿ ν chat ó expect ڿ
  ǳʶٰ ؾѴ.   츮 ATZ , Hayes-compatible 
     ְ, (OK)  ٸ.  chat 
  ȭȣ ̾ , CONNECT ޼ ٸ. ⼭
  ٽ  ڿ ް Ǵµ, 츮  ƹ͵  ʾұ
  ̴. ׷ ٽ α Ʈ ٸ ȴ. Chat ũƮ
    ״ Ѵٴ  ϶.  -v ɼ syslog
   local2 facility   Ȱ  chat log .
  (facility :   ̵ log ޼ ̷Ʈϵ
  syslog.conf ߴٸ,  ȭ   ⶧ chat α׵
  ȣ    ü chat ũƮ Ʈ .)

  ڵ ps  ̿ process command   ֱ  chat
  ũƮ command line ϴ  ټ ϴ. ׷Ƿ
   chat script dial-c3po Ҹ ϳ ȭϿ μ ̷
     ִ.  -f 'ȭϸ' ɼ   command
  line  ϴ  ȭϷκ ũƮ о  ִ.
  ׷  pppd 'ֹ'   ̴.

           # pppd connect "chat -f dial-c3po" /dev/cua3 38400 -detach \
                    crtscts modem defaultroute

  ̾  ũƮ    ɼ ̿ܿ, 츮 command
  line   ɼ ߰Ͽ: pppd ֿܼ ޶ 
  ׶ μ ǵ ִ -detach̴. , modem Ű
  𵩿  -ȭ ɱ̳     ø ġ
  Ư - Ѵ.    Ű带  ʴ´ٸ,
  pppd Ʈ DCD    ̸ ׷  
  ý ڱ ٵ簡 ϴ 츦  ˾ Ѵ.
     ټ  ̴; chat ξ  
  ũƮ   ִ.      chat 
    ̸ ϴ ڿ   ִ.  
  ڿ   ȭ ȭ̰ų, ȭ⸦  ʾ 쿡
   BUSY, NO CARIIER  ޼̴. chat ̸ ٷ
  ˾ ϱ ؼ time out ٸ⺸ٴ  chat
  ũƮ ۿ ABORT Ű带    .

           $ chat -v ABORT BUSY ABORT 'NO CARRIER' '' ATZ OK ...

  ̿  ε,  TIMEOUT ɼ chat ũƮ
  ߰ν timeout    ִ.  ڼ  chat(8)
  Ŵ  оƶ.  ,     
  chat ũƮ  ʿ  ̴.  ,  ý α
  Ʈ  ʾ , BREAK ų ĳ   
  ̴.  expect ڿ sub-ũƮ ߰ν ̸ ذ
   ִ. װ  еǾ ִ ũƮ ü  ü 
  send- expect-ڿ  Ǿִ. sub-ũƮ ߴ
  ڿ  ޾ ʾ  ȴ.   츮 chat
  ũƮ     ִ.

           ogin:-BREAK-ogin: ppp ssword: GaGariN

  , chat  ý α Ʈ  ,
  sub-ũƮ ù BREAK , ٽ α Ʈ ٸ
  ȴ. Ʈ Ÿ, ũƮ ҿ  ӵǰ, 
  ׷ ϸ  Բ  .

  8.6.  Debugging Your PPP Setup

  ⺻, pppd    ޼ syslog daemon
  facility αѴ. ֿܼ syslog ̷  ׳
     syslog.conf ùӸ ̰ Ϸ
  ̷Ʈϵ ϴ  ؾѴ.

             daemon.*                /var/log/ppp-log

    PPP ¾    ʴ´ٸ  αȭ
  ߴٺν  ߸ǰ ִ°   ִ. ̰  
   ʴ´ٸ  ɼ ̿ ܺ  output ϰ  
  ִ. ̰ syslog ų   control packet 
  pppd log .  ޽ deamon facility .

  ,    kdebug ɼǿ ϴ pppd 
  Ŀ-   ϰ ϴ ̴. ̰  
  bitwise OR   .: 1 Ϲ  ޼, 2
  HDLC   ޼ , ׸ 4 HDLC 
    ̹ Ʈ̴. ̷ Ŀ  ޼
  ϱ Ͽ,  /proc/kmsg ȭ е syslog 
  Űų klogd Ѿ Ѵ.  Ŀ  syslog
  Ŀ facility  Ѵ.

  8.7.  IP Configuration Options

  IPCP ũ ð ִ ξ IP parameter ϱ Ͽ
  ȴ. Ϲ  peer   ⺻κ ٲٷ
  ϰų,   Ű IPCP Configuration Request packet
   𸥴. ̵ ſ ,  ȣƮ ˻  
  Ǿ ִ³Ŀ  װ ϰų źϰ ȴ.  pppd 
    IPCP ɼǵ ſ ش. ̵ command line ɼǿ 
    ؼ  Ѵ.

  8.7.1.  ChoosingIPAddresses

    츮 c3po ȭ ɰ IP ũ . ũ
   ʿ Ư IP-ּҸ ϵ ϴ غ .  
  local IP-ּҷ 츮 vlager ּҸ ߰, c3po  ڽ 
  ֵ ߴ. ׷  ũ ̳ Ǵٸ ʿ  ּҸ
    ϴ  ſ ϴ. pppd ̿ شϴ
   ȭ   ִ.  Ư ּҵ Ͽ, 
  Ϲ pppd  ɼ   ִ.

           local addr:remote addr

  ⼭ local_addr remote_addr 4κ ̷ ּ ǥ̰ų
  ȣƮӵ ־Ѵ. ̰ pppd ù° ּҸ ڽ
  IP-ּҷ, ι° peer ּҷ ϵ .  peer  
  ͵ IPCP   źѴٸ IP-ũ   ̴.

    peer ڵ  ּҵ ޾Ƶ ʰ  local
  address Ѵٸ remote_addr κ θ ȴ. ,
  130.83.4.27̶ IPּҸ J vlager ϰ ʹٸ  command
  line 130.83.4.27: ϸ ȴ. ϰ, remote_addr
  ϱ ؼ local_addr κ θ ȴ. ⺻, pppd
   ȣƮӰ  ּҸ Ѵ.

   PPP   Ŭ̾Ʈ Ʋ鿡 ּҸ 
  Ѵ: ּҵ  ȭ ɷ ǰ, ٽ α׿
   Ѵ. ׷ ̾ ,   ſ 
  ּҸ  ٴ pppd κ Ư IP-ּҸ 䱸ϴ 
  ʴ´ٴ   ؾ Ѵ. ̰  local_addr  
  ƾ Ѵٴ  ǹѴ. ٿ,  local host ּҸ
  ϴ  peer ϴ IP-ּҸ ϵ ϴ noipdefault
  ɼ ؾ Ѵ.

  8.7.2.  Routing Through a PPP

  Ʈũ ̽  Ŀ, pppd Ϲ ȣƮ θ
  peerԸ ¾ ̴.   ȣƮ  ִٸ, 
  '' ִ peer  ȣƮ Ǳ⸦  ̴. ; ٽø
  Ʈũ ΰ Ǿ Ѵ.

  츮 ̹ ⺻ɼ   ⺻ η Ѵٴ 
  캸Ҵ.  ɼ  ȭ  PPP   ͳ
  Ʈ̷    ſ ϴ.

   ݴ ,  ý ϳ ȣƮ  Ʈ̷
  ɶ,    ϴ.  , loner 
  ǻ    ϲ 츦    ִ. PPP
   vlager ϴ , ״  subnet ּҸ  
  ִ. vlager, pppd  loner proxy ARP   ִ
  ɼ νϴ proxyarp ɼ   ִ. ̰ ڵ
  loner  ξ忡 ִ  ȣƮ   ֵ
  .

  ׷  찡 ó  ʴ. ,   ÿ
  Ʈũ ũϴ Ͱ   ̴. ̴ Ȯ Ʈũ
  θ ߰־߸ Ѵ. ֳϸ ̵ Ʈũ ׵ ڽŸ
  ⺻ ε  ֱ ̴.  ܿ, PPP ũ ⺻ η
  Ͽ loop ϰ Ǵ 쿡  peer  Ǵ ,
  peer Ǿ ִ  ð   ġ Ź ϴ ó
     𸣰 ȴ.

   ,      ÿ  Ҵٰ .
   B Ŭ Ʈũ subnet3  ׵ ڽ IP Ʈũ
  ѹ 191.72.3.0 ̿Ͽ ̴ Ѵ. ׵ 
  Ÿ̽  Ʈϱ  PPP    ̴ݿ
  ϱ⸦  ̴. ٽ, vlager Ʈó ൿϰ, ׵
  peer sub-etha Ҹ 191.72.3.1.. IPּҸ  ȴ.

  Sub-etha vlager  , װ Ϲ vlager ϴ ⺻
   Ʈ  ̴. vlager 츮 sub-etha ġ
  subnet-3  Ʈũ θ ġؾ Ѵ. ̸ , 츮
  ׷Ա   pppd -ip-up-   ִ. ̰
    ũƮ̰ų PPP ̽  ǰ  Ŀ
  Ǵ /etc/ppp ġϴ α׷̴. װ , װ
    ĶͿ  ȴ.

             ip-up iface device speed local addr remote addr

  ⼭ ifcae ǰ ִ Ʈũ ̽ ϰ, device
  ǰ ִ ø ġ θ(stdin/stdout ȴٸ
  /dev/tty)̸, speed ġ ӵ̴. local_addr remote_addr
  ũ   :  4 κ  IP-ּҵ ش. 츮
  , ip-up ũƮ Ƹ    ϰ  ̴.

             #!/bin/sh
             case $5 in
             191.72.3.1)            # this is sub-etha
                     route add -net 191.72.3.0 gw 191.72.3.1;;
             esac
             exit 0

  ̿  , /etc/ppp/ip-down PPP ũ װ   ip-up 
   ൿ ϱ  ȴ.

  ׷  ȹ  Ϻ  ƴϴ. 츮  PPP
  ȣƮ鿡  ̺  ,   ȣƮ
  ٸ  Ʈũ  PPP ũ ؼ ƹ͵  Ѵ.
  ׷    ȣƮ sub-etha ִ ׵ ⺻ Ʈ
    ְ,   ȣƮ vlager ϴ ⺻
  θ ϴ ̰ ״ ū  ƴϴ.  ̰ ٷ
  ׷ 찡 ƴ϶  gated    ϸ
  ȴ. vlager  Ʈũ θ ϰ  Ŀ,  
  ݿ پִ  ȣƮ鿡 ο θ ˷ ̱
  ̴.
  8.8.  Link Control Options

  տ 츮 ̹ ũ Ư ϱ  Link Control
  Protocol,LCP ٷ.

  LCP  Ǵ ΰ  ߿ ɼǵ maximun receive unit
  Asynchoronous Control Character Map̴.  LCPɼǵ ֱ
  , ⼭ ϱ⿡ ʹ ȭ Ǿ ִ  ̴.
  װ͵  ڼ ˾ƺ RFC-1548 ϱ ٶ.

  , async map Ҹ Asynchoronous Control Character Map
  ݵ  ־ ϴ control character ؾ ϴ ȭ
   񵿽 ũ  ȴ.    ߸ 
    XOFF ޾   𸣱  Ʈ
  handshake  XON XOFF character Ƹ   
  𸥴. ٸ ĺڵ Ctrl-](ڳ escape character) Ѵ.
  PPP ASCII ڵ 0 31  ̶ async map ϸ
   ش.

  async map  ASCII ι(ASCII 31) شϴ ּ  ڸ
   32-Ʈ  Ʈ̴.  Ʈ Ǹ, ũ  װ
    ϴ ڴ ݵ escapeǾ ȣ .
  ϸ鼭 async map  control character escapeǴ
  0xffffffff ߾.

   peer  ͵  Ư  ϰ  control
  character escape ʿ䰡 ٰ ϱ , asyncmap ɼ
  Ͽ ο asyncmap pppd   ִ. ,  ^s
  ^Q(ASCII 17 19, Ϲ XON XOFF) escape Ǿ Ѵٰ  ,
    ɼ   ִ.

             asyncmap 0x000A0000

  ִ  (Maximum Receive Unit), Ȥ MRU peer 츮
  ް ϴ ִHDLC ӵ ũ⸦ .  κп MTU(Maximum
  Transfre Unit:ִ  ) ø  ְ,   
   . MTU Ŀ Ʈŷ ̽ Ķ̰, 
  ̽   ִ ִ  ũ⸦ Ÿ. MRU
  MRU  ū  ӵ  ʵ  ̿ ִ
  ܼ  ̴.; ׷ ұϰ ̽ ּ
  1500ӱ   ־ Ѵ.

  ׷Ƿ MRU ϴ   ũ    ִ 
  ƴ϶   ִ ó ִ ΰ ϴ ̴. 
  ũ  ;Ƽ α׷ ϱ⸦ Ѵٸ, MRU 
   296 ִ   ̷  ̵ݾ ū Ŷ(, FTP
  )  Ŀ ""ϰ   ̴. pppd MRU
  296 ߶ ϱ ,  mru 296̶ ɼ ָ ȴ.
  ׷  MRU  VJ    ʵ  ʾ
   (Ϲδ )  ˾ƸԴ´.

  pppd ũ Ǳ  ȯǴ  û ִ ڵ 
   μ ü  ϴ ξ LCPɼ Ѵ.
     ϴ Ȯϰ ˰  ʴٸ, ׳ δ 
   .

  , LCP  ޼鿡 Ǵ   ɼ ִ. PPP
  ΰ ޼, Echo û Echo ,  Ѵ. pppd  
   ũ   ϱ  Ѵ.  ̰͵
  ʷ ǥϴ ð Բ lcp-echo-interval ɼ  ϰ  
  ִ.  ð    ȣƮκ  ŵ ٸ pppd
  Echo û ߻Ű, peer Echo  ⸦ ٸ. 
  peer  ؿ ʴ´ٸ, ũ   û  Ŀ
  .  ڴ lcp-echo-failure ɼ Ͽ   ִ.
  ⺻       ʵ Ǿ ִ.

  8.9.  General Security Considerations

  ߸  PPP  ȱ  ū  ʷѴ. ̰
  ƹ ڳ  ̴  ϴ ־ ̴. 
  忡  PPP  ϰ ϴ   غ
  ϰڴ.

  pppd   ϳ Ʈũ ̽  ̺ ϴµ
  root 䱸ϴ ̴. Ϲ    root
  Ѽ Ǯ ̴. ׷ pppd ڵ鿡  Ȱ
  õ ɼǵ ϵ Ѵ. ̷ ɼǵ ϰ 
  ڵ κ ȣϱ ,  忡  ü
  ⺻ ɼǵ /etc/ppp/options ȭϿ ִ  Ѵ. ׵
  authentification ɼǰ  ͵ ڵ鿡    
     å  ȣ  ش.

  ,  ڽŵ  ýκ PPP ϴ  ȣؾ Ѵ.
  ٸ ó  ȣƮ о Ͽ, ׻ peer  
     ־ Ѵ. ߰  ܺ ȣƮ
  ׵ ϴ  IP-ּҵ  ϵ ؾ  ּ 
   ؾ Ѵ.  忡   ٷ.

  8.10.  Authentication with PPP

  8.10.1.  CHAP versus PAP

  PPP    ý Ƹ ý peer  ڽ
  ΰ    ϳ   䱸  𸥴.  
  ٷ Password Authentication Protocol(PAP), ׸ Challenge Handshake
  Authentication Protocol(CHAP)̴.  Ǿ, ũ  
  ٸ ʿ  ڽ  ȭ ̵ ȭ ޴ ̵
  䱸ϰ ȴ. ׷Ƿ  Ʒ ϴ ʰ ޴ 
  ϰ   'Ŭ̾Ʈ' ''  ټ ϰ ص
   ̴. PPP   peer ٶ   Ȯϴ
  Ǵٸ LCP  û ν    ִ.

  PAP Ϲ α     Ѵ.
  Ŭ̾Ʈ ڸ (Ϲδ ȣȭ)ȣ   ڽ
  ϰ   ڽ  Ÿ̽ װ  . 
   ø   ȣ ˾Ƴ ϴ   ݺǴ
  '' ݿ ϴ.

  CHAP ̷    ʴ. CHAP (, )
    "challenge" ڿ  ȣƮ Բ
  Ŭ̾Ʈ . Ŭ̾Ʈ ȣƮ  ȣ, challenge
  ؼ,ã ϰ,  ڿ  ϳ hashing Լ
  ̿ؼ ȣȭѴ.   Ŭ̾Ʈ ȣƮ Բ 
  ǵư.      ϰ,  
  ǵƿԴ  Ȯϰ Ŭ̾Ʈ Ѵ.

  CHAP ٸ Ư¡,  Ŭ̾Ʈ  Ҷ 
   ʰ, Ŭ̾Ʈ ٸ ħڿ  ٲ ʾҴ, 
   ȭ ٲģٵϴ, Ȯϱ  Ư ð ΰ
  challenge Ŭ̾Ʈ .

  pppd  /etc/ppp/chap-secrets ppp-secrets ٸ ȭϷ
  CHAP PAP  ΰ  Ű Ѵ.  ϳ ٸ ȭ
   ٸ    ,  CHAP PAP  
  Ǹ Ʈ ް ǰ  ޴´.
  ⺻, pppd ݼκ  䱸  ݼ
  䱸  ű⿡ Ͽ  ϰ ȴ. CHAP PAPٴ
  ξ  ϱ , pppd ϸ CHAP ϷѴ. 
  peer װ  ʴ´ٰų  pppd  ý chap-
  secret ȭϷκ CHAP secret ã Ѵٸ, PAP ٲ.  PAP
     ʴٸ  źϰ ǰ,  
   ȴ.

  ̷   ȴ. , ־  Ű忡 ,
  pppd peerpeer  ڽ  ϵ 䱸ϰ ȴ. pppd CHAP
  PAP Ÿ̽ peer  secret ϴ ϴ  CHAP PAP
  ϵ  ̴. Ư   Ѱ  ٸ ɼǵ
  ִ. ⼭   ٷ ʰڴ. pppd(8) ޴ ϵ
  ϶.

    PPP   ýۿ Ű ׵ ڽ ϵ
  Ϸ, ݵ auth ɼ ü /etc/ppp/options ȭϿ
  ֵ ϰ,  ýۿ شϴ йȣ chap-secretȭ
  ־ Ѵ.  ý CHAP  ʴ´ٸ, ׸  pap-
  secret ȭ ÷϶.     ȣƮ   
    ý۵  ϰ   ִ.

     PPP ΰ secret ȭ pap-secrets Chap-
  secretsȭϿ ؼ ٷ ̴. ̵ /etc/ppp ġϸ
  Ŭ̾Ʈ, , йȣ, κ ̷  
     IP-ּҵ Ʈ Ѵ. Ŭ̾Ʈ
   ʵ ؼ CHAP PAP  ٸ, peer  
   ϴĿ ϰų Ȥ  츮 Բ  䱸ϴĿ
  ޷ִ.

  8.10.2.  The CHAP Secrets File

  CHAP    ڽ  ϱ ؼ, pppd pap-
  secretsȭϿ  ȣƮ  Ŭ̾Ʈ ʵ带 ã, CHAP
  Challenge   ȣƮ   ʵ带 ã´. peer
   ڽ ϵ ٽ Ͽ,  ܼ ݴ
  ٲ:pppd  ȣƮ  Ŭ̾Ʈ ʵ带
  ã,(Ŭ̾Ʈ CHAP 信 )  ȣƮ 
  ʵ带 ã´.

  Ʒ vlager   chap-secrets ȭ̴.

      # CHAP secrets for vlager.vbrew.com
      #
      # client          server            secret                addrs
      #-------------------------------------------------------------------
      vlager.vbrew.com  c3po.lucas.com    "Use The Source Luke" vlager.vbr
      c3po.lucas.com    vlager.vbrew.com  "riverrun, pasteve"   c3po.lucas
      *                 vlager.vbrew.com  "VeryStupidPassword"  pub.vbrew.

  c3po PPP ̷  c3po vlager CHAP Challenge
   CHAP   ڽ ϵ Ѵ. pppd 
  vlager.vbrew.com  Ŭ̾Ʈ ʵ带 ã chap-secrets ȭ
  ˻ϰ c3po.lucas.com  ʵ带 ã,   ù°
  ٿ ãƳ.  challenge ڿ secret(Use The Source
  Luke)κ CHAP  ܳ, װ c3po .

  ÿ pppd Ư challenge ڿ ϰ ְ Ȯ 
  ȣƮ vlager.vbrew.com ϰ ִ c3po  CHAP
  challenge ۼѴ. c3po  츮 ̾߱ߴ  CHAP
   , װ vlager ǵ ش.  pppd CHAP
  κ Ŭ̾Ʈ ȣƮ(c3po.vbrew.com) ̾Ƴ,
  Ŭ̾Ʈμ c3po ´ κ ִ chap-secret ȭϷκ
  ã, μ vlager ִ ã´. κ°    ϰ,
  ׷ pppd CHAP challenge secert riverrun, pasteve ȣȭ ϰ
    c3po CHAP  Ѵ.

  ׹°  ʵ ù° ʵ忡  Ŭ̾Ʈ鿡 شϴ
  IP-ּҵ Ѵ.  ּҵ 4 κ ̷ų, resolver
   νĵǴ ȣƮϰ̴.   c3po IPCP ߿
  Ʈ  ʴ IP ּҸ ϱ⸦ Ѵٸ,  䱸 ǰ,
  IPCP  ̴.   ȭϿ, ׷Ƿ c3po 
  ڽ IP-ּҸ ϴ  ѵȴ.  ּ ʵ尡 ִٸ
   ּҵ鵵 ȴ.; - Ŭ̾Ʈ   ϵ
  ش.

  chap-secrets ȭ °   ȣƮ Ŭ̾Ʈ,
  ʵ * ϱ   ȣƮ vlager PPP ũ
   ֵ ش.  䱸 װ secret ˰,
  pub.vbrew.com ؾ Ѵٴ ̴. pppd ׻ /Ŭ̾Ʈ
  ¦ ̷絵  ֱ  ϵī ȣƮ ϴ
  entry Ƹ secrets ȭ 𿡼  𸥴.

   pppd  secrets ȭϷκ ȣƮ ̸ Ǵ
  ˾ƺ.  ߴ ,  ȣƮ ׻ CHAP Challenge
  Ŷӿ ִ peer ؼ ȴ.  ȣƮ ⺻
  gethostname(2) Լ ؼ .   ý۸ 
  ѵ ȣƮ شٸ   domain ɼ ؼ pppd
  domain name ־ Ѵ.

             # pppd ...domain vbrew.com

  ̰ Brewery domain name   õ Ȱ Բ
  vlager δ.  ȣƮ  progpppd  ٸ
  ɼǵ usehostname name̴.  "local:varremote" command
  line    IP ּҸ ־ , local 4 : е
  ڸ ϴ namḛ, pppd ̸  ȣƮ  ̴.
   ڼ  pppd(8) Ŵ  ϱ ٶ.

  8.10.3.  The PAP Secrets File

  PAP secerts ȭ CHAP ſ ϴ. ó  ʵ ׻
  ڸ   ִ; ° PAP secret  ִ. 
   û ö, pppd  ȣƮ ʵ尡 
  ϸ,  ʵ û  ڸ   ˻Ѵ.
  peer ڽ   ̷, pppd   
  ڸ   ʵ Բ   secret ϰ ʵ
    ȣƮ Ѵ.

   PAP secrets ȭ Ƹ   ̴.

          # /etc/ppp/pap-secrets
          #
          # user          server          secret          addrs
          vlager-pap      c3po            cresspahl       vlager.vbrew.com
          c3po            vlager          DonaldGNUth     c3po.lucas.com

  ù°  츮 ڽ c3po ϱ  ȴ. ι° 
   c3po ̸ ڰ  ڽ 츮 Բ Ǵ 
  Ÿ ش.

  ù° ÷ ִ vlager-pap ̸ 츮 c3po 
  ڸ̴. ⺻ pppd  ȣƮ ڸ Ѵ.
  ׷  name ڿ  user ɼ Ͽ ٸ ̸
    ִ.

  peer   pap-secrets ȭϿ entry   , pppd
   ȣƮ ̸ ˾ƾ Ѵ. װ ˾Ƴ   
   ݵ peer ȣƮڿ  remotename̶ Ű带
  ؼ command line ؾѴ.    
  c3po  , 츮 ݵ  ɼ pppd command line
  ־ Ѵ.

             # pppd ...domain vbrew.com

  ׹° κп(׸  ڿ   κ), CHAP ׷ ó
    IP-ּҵ Ư ȣƮ    
  ִ. peer  Ʈ ִ ּҵ鸸 û  ִ.
  ȭϿ, 츮 c3po װ  IP ּҸ ϵ ϰ
  ִ.

  PAP δ ټ ϴٴ  ϶. ׸ ϴٸ
  CHAP ϱ⸦ Ѵ. ׷ ⿡ PAP  а
  ٷ  ̴. PAP ϴµ  ִٸ pppd(8) Ŵ
     PAP Ư¡ ؼ ãƺ ϶.

  8.11.  Configuration a PPP Server

  pppd   ؼ  command line  ɼ ߰
  ֱ⸸ ϸ ȴ.  ̻δ,  ppp Ư  ϳ
     α  pppd ɼ ִ ũƮ ָ ȴ.
     /etc/passwd   ߰ϸ ȴ.

             ppp:*:500:200:Public PPP Account:/tmp:/etc/ppp/ppplogin

  ,     Ͱ ٸ uid gid 
  𸥴.  passwd  ̿ؼ   йȣ οؾ
  Ѵ.

  ppp α ũƮ Ƹ   ̴.

             #!/bin/sh
             # ppplogin - script to fire up pppd on login
             mesg n
             stty -echo
             exec pppd -detach silent modem crtscts

  mseg  ٸ ڵ  tty ⸦ Ұϰ Ѵ.
  , write    ִ. stty   echo . ̰
  peer   ehcoǾ ǵ ü ֱ  ʿϴ. 
  ־  ߿ pppd ɼ -detach ̴. ̰ control
  tty pppd detachϴ   ̴.  츮  ɼ
   ʴ´ٸ pppd ׶  ǰ,  
  ũƮ   𸥴. ̷  ø   
  ȴ. silent ɼ pppd ϱ  ȭŴ  ý
  Ŷ   ٸ ϰ Ѵ. ̰ ȭŴ  ý
  PPP Ŭ̾Ʈ  ʹ   timeout Ǿ   
  ش.   peer ӿ  ʾҴ ϴ DTR 
  pppd watch , crtscts ϵ handshake ۵Ų.

  ̷ ɼǵ ̿ܿ,        
  ִ,   pppd command line   ϰų,
  ü ɼǿ    ִ. man     
  ݿ  ɼ Ѱ  Ϳ  Ǹ ϰ ִ.

