Example explanation of WAN routing technology

We assume that readers have a certain degree of understanding of IP Protocol (IP protocol can never maintain an IP network), such as at least know the structure of IP address, category and subnet, subnet mask concept, and have a certain computer basics. In the configuration of routers, as long as the computer's serial port through the router's own dedicated cable to the console, the use of such as HyperTerminal or Netterm software.

There is only one network card (an IP address) in the network. Any host can only directly access the machine in the Notebook network. The router is equivalent to a host of multiple network adapters, each of which can communicate directly with a subnet. As we know from the above figure, the two networks are connected mainly by establishing a WAN interconnect subnet during the intervening period. There are only two machines in this subnet, that is, the routers on either side, and of course its subnet mask is 255.255.255.252. As long as the seiral port of router A and B is on the same subnet, because their Ethernet ports belong to A and B nets respectively, we establish a channel between A and b nets. If the host in Network A has a gateway set to router A, its information can be forwarded to B network via router A and B.

We use the most widely used Cisco 2501 router in the example, which has a simple physical structure, a network interface with only two serial ports and a Ethernet port, but supports full routing capabilities. The protocol used is TCP/IP, because it is now very outdated to use other protocols such as IPX and NetBEUI.

Instance 1: Connect a LAN with a B LAN via Cisco 2501
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Assume the experimental conditions are as follows:

A net: 202.96.199.0--202.96.199.255

B Net: 202.97.76.0--202.97.76.31

DNS server:202.96.199.2 (Master), 202.96.199.3 (Ready)

Domain: xxx.com

Wan Interconnect: Requires a subnet containing 4 IP addresses (2 available IP),

Set as: 202.98.0.0--202.98.0.3, where 202.98.0.1 to a net, 202.98.0.2 to B network

Interconnect line rate: 128kbps

The specific network parameter allocation table is as follows:

Project

A network

B net

Network number

202.96.199.0

202.97.76.0

Subnet mask

255.255.255.0

255.255.255.224

Owning domain

xxx.com

yyy.com

Ethernet Address

202.96.199.1

202.97.76.1

Internet address

202.98.0.1

202.98.0.2

Line rate

128kbps

with left

Domain name server

Main: 202.96.199.2

Prepare: 202.96.199.3

Same-left

First go to the router: Connect your computer serial port to the router's console port, and log in using software such as Netterm or HyperTerminal.

router>en:

passwd:****** (enter Super password)

Global configuration: (A, b net)

router#conf terminal (switch to configuration State)

Router (config) #enable secret my-root-password (define Super Password

Router (config) #ip host router-a (define router name, B network router-b)

Router (config) #ip domain-name xxx.com (define the owning domain name, b net is yyy.com)

Router (config) #nameserver 202.96.199.2 (define primary Domain name server)

Router (config) # NameServer 202.96.199.3 (definition of the standby Domain name server)
Router (config) #ip classless

Router (config) #line vty 0 4

(defines 5 Telnet virtual terminals, that is, 5 people can log on to the router at the same time)

Router (config-line) #password my-telnet-password (define telnet password)

Router (config-line) #exit

Router (config) #exit

Address and routing configuration:

/****** A Network router ******/

Router-a #conf T (switch to configuration State)

Router-a (config) #int E0 (Configure Ethernet 0)

Router-a (config-if) #description the LAN port to me local network (port description)

Router-a (config-if) #ip add 202.96.199.1 255.255.255.0

(Defines the Ethernet IP address, the subnet mask is represented as a Class C network)

Router-a (config-if) #no shutdown (activation port)

Router-a (config-if) #exit

Router-a (config) #int s0 (configuration serial 0)

Router-a (config-if) #description the WAN port link to router-b (port description)

Router-a (config-if) #ip add 202.98.0.1 255.255.255.252 (defines an interconnected WAN IP address)

Router-a (config-if) #bandwidth 128 (define port rate, in Kbps)

Router-a (config-if) #no shutdown (activation port)

Router-a (config-if) #exit

Router-a (config) #ip Route 202.97.76.0 255.255.255.224 202.98.0.2

(define static routing, access to the End-to-end LAN via gateway, IP to IP address of the End-to-end WAN)

Router-a (config) #exit

ROUTER-A#WR m (Save configuration)

/****** B Network Router ******/