Transcript IETF 報告 UDLR-WG

How to connect to the Internet
1998/12/09
KEIO University, JAPAN
Mikiyo Nishida/[email protected]
Overview of this section
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Internet connectable hardware/OS
Why use the UNIX OS?
Host connect to the network
Server side configuring
Internet connectable hardware
• Hardwares
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Workstation
PC (Personal Computer)
Set Top Box
Game machine and others
PDA
Internet connectable OS
• UNIX Family
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FreeBSD
BSD/OS
Linux
SunOS
• Windows Family
– Windows 95/98
– Windows NT
Why use the UNIX OS?
• The Internet was developed on UNIX
• UNIX’s TCP/IP stack, and service daemons
are more reliable than Windows
• but, Windows can connecting network easy
...Generally
Front-end : Windows or UNIX
Back-end : UNIX
Host connect to the network
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Configuring Network Interface
Configuring Routing Table
Configuring Name Resolver
Automatic network configuration
Configuring Network Interface
• Network Interface has global unique IP
Address
• Host is belong to a network - Network
Interface has netmask
Setting IP Address and Netmask
• Use command “ifconfig”
• “ifconfig” command attach/detach/modify
NIC’s network information
– example:
# ifconfig ed0 inet 192.168.1.2 netmask 255.255.255.0
IP Address and Netmask
• IP Address is separated 2 parts
– Host Address
• Indicate Host ID
– Network Address
• Indicate Network ID host belong
• Netmask indicates Network Address part of
IP Address
Special IP Address(1)
• Private IP Address
– Not use for global Internet
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.16.255.255
192.168.0.0 - 192.168.255.255
• Localhost (indicate MYSELF)
127.0.0.1
Special IP Address(2)
• Datalink Broadcast Address
– All nodes in the same network segment
255.255.255.255
• Network Address
– Host Address part’s all bit are 0
192.168.1.0 / netmask 255.255.255.0
• Network Broadcast Address
– Host Address part’s all bit are 1
192.168.1.255 / netmask 255.255.255.0
Configuring Routing Table
• For the communication, Host must send
packet to router
• Routing Table is used where send the packet.
Setting Route in Routing table
• Command “route” set/unset/change route in
routing table
– example
#route add 192.168.0.0 10.0.0.1
#route add default 192.168.1.2
Routing Table
• Routing table has mapped data
route (Destination Network - Next Hop Router)
• “default route” is route for unknown
destination network
• Generally, End-node (Host) set “default
route” to border router
Configuring Name Resolver
• TCP/IP Stack must resolve the matching
hostname and IP Address
• For resolving, TCP/IP stack queries DNS
Server
Name Resolver Setting
• Name Resolving DNS Server is describing
“/etc/resolv.conf”
• If use statically hostname and IP Address
table, describe “/etc/hosts”
Example of Name Resolver
Setting
• /etc/resolv.conf
DOMAIN sfc.wide.ad.jp
NAMESEREVR 202.217.0.99
SEARCH sfc.wide.ad.jp. wide.ad.jp.
• /etc/hosts
myhost
yourhost
192.168.9.8
10.0.0.1
Automatic Host Configuration
• DHCP - Dynamic Host Configuration
Protocol
– Automatically configure host setting
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IP Address
Netmask
DNS Server Address
Default Route
Server side configuration
• DNS (bind) Entry
• Routing Daemon