路由器是计算机网络的桥梁，是连接IP网的核心设备。它不仅可以连通不同的网络，还能选择数据传送的路径，并能阻隔非法访问。对初学者来说，路由器的配置并不是一件易事。现以Cisco 2600路由器为例，将Cisco路由器配置的常识介绍给大家。
一、连接
1.用Cisco 2600路由器自带的一条串行电缆将路由器的Console口与1台计算机串口相连。
2.启动Windows 2000后，执行以下操作：“开始→程序→附件→通讯→超级终端”，在“连接描述”对话框的名称一栏中输入超级终端名，点击“确定”。
3.在“连接到”窗体中的“连接时使用”栏选择“COM1”，单击确定。在弹出的“COM1属性”窗体中进行端口设置。
设置结束，打开路由器电源，就会出现路由器的启动信息。这时就可以像在终端一样对路由器进行操作了。
二、配置
路由器的配置操作都必须连接到路由器的终端上，在Cisco路由器操作系统IOS的提示符下进行操作。
常用配置方法如下：
1.配置以太网络接口的IP地址
Router> enable '进入特权模式
Password： '特权用户口令
Router# configure terminal '进入配置模式
Enter configuration commands one per line. End with CNTL/Z.
Router¬config # interface Ethernet 0 '进入外部以太网口配置
Router¬config-if # ip address 192.168.0.11 255.255.255.0 '进入AUI0接口的IP地址配置为192.168.0.11，子网掩码为255.255.255.0。
2.配置静态路由表
Router> enable
Password：
Router# config terminal
Enter configuration commands one per line. End with CNTL/Z.
Router¬config # ip route 192.168.2.0 255.255.255.0 192.168.0.1 '配置进入AUI0接口的IP地址。
3.配置动态OSPF路由
Router> enable
Password：
Router# config terminal
Enter configuration commands one per line. End with CNTL/Z.
Router¬config # router ospf 1
Router¬config-router # network 192.168.0.0 0.0.0.255 area 0.0.0.0
其中的192.168.0.0是子网的地址，也可以是路由器上的接口的IP地址或OSPF路由器所用接口的网络地址；而0.0.0.255掩码后面为OSPF所用的域。
4.查看以太网接口0的状态
Router> enable
Password：
Router# show interface Ethernet 0 '显示以太网接口0的状态。
5.查看路由器的当前配置
Router> enable
Password：
Router# show run '显示路由器的当前配置
上述内容只是一些常见的路由器配置方法，要想全面掌握路由器的配置，还需要有扎实的知识和丰富的实际经验。初学者可以通过使用模拟软件来学习配置,RouterSim就是很好的模拟软件，想试试身手的朋友可以去下载来用用。
三．Cisco 路由器 VPN典型配置
Current configuration
!
version 12.0
sevice timestamps debug uptime
sevice timestamps log uptime
sevice password-encryption
!
hostname bluestudy1
!
enable passsword cisco
!
memory-size iomem 25
ip subnet-zero
no ip domain-lookup
!
interface Tunnel0
ip address 172.16.101.1 255.255.255.0
no ip directed-broadcast
ip mtu 1467
tunnel sourece 199.1.1.2
tunnel destination 199.1.2.2
!
interface serial0/0
no ip address
no ip directed-broadcast
encapsulation frame-relay
no ip mroute-cache
frame-relay lmi-type ansi
!
interface serial0/0.1 point-to-point
description connected to internet
ip address 199.1.1.2 255.255.255.248
no ip directed-broadcast
ip nat outside
no arp frame-relay
frame-relay interface-dlci 111
!
!
interface ethernet0/0
ip address 172.16.1.1 255.255.255.0
no ip directed-broadcast
ip nat inside
!
router eigrp 100
network 172.16.0.0
!
router rip
version 2
network 172.16.0.0
no auto-summary
!
ip nat pool bluestudy 199.1.1.3 199.1.1.10 netmask 255.255.255.248
ip nat inside sourece list 2 pool bluestudy overload
ip nat inside sourece static 172.16.1.3 199.1.1.5
ip classless
ip route 0.0.0.0 0.0.0.0 srial0/0.1
ip http server
!
access-list 2 permit 172.16.1.0 0.0.0.255
snmp-server community public RO
!
line con 0
exec-timeout 0 0
password cisco
login
transport input none
line aux 0
line vty 0 4
password cisco
login
!
end
1.Cisco 2600 Configuration with IPSec
Current configuration
!
version 12.0
sevice timestamps debug uptime
sevice timestamps log uptime
sevice password-encryption
!
hostname bluestudy1
!
enable passsword cisco
!
memory-size iomem 25
ip subnet-zero
no ip domain-lookup
!
crypto isakmp key policy 1
authentication pre-share
group 2
crypto isakmp key slurpee-machine address 172.16.101.2
!
crypto ipsec transform-set test ah-sha-hmac esp-des esp-sha-hmac
!
set transform-set test
!
crypto map bluestudy 10 ipsec-isakmp
set peer 172.16.101.2
set transform-set test
match address 101
!
interface Tunnel0
ip address 172.16.101.1 255.255.255.0
no ip directed-broadcast
ip mtu 1467
tunnel sourece 199.1.1.2
tunnel destination 199.1.2.2
crypto map bluestudy
!
interface serial0/0
no ip address
no ip directed-broadcast
encapsulation frame-relay
no ip mroute-cache
frame-relay lmi-type ansi
!
interface serial0/0.1 point-to-point
description connected to internet
ip address 199.1.1.2 255.255.255.248
no ip directed-broadcast
ip nat outside
no arp frame-relay
frame-relay interface-dlci 111
!
!
interface ethernet0/0
ip address 172.16.1.1 255.255.255.0
no ip directed-broadcast
ip nat inside
!
router eigrp 100
network 172.16.0.0
!
router rip
version 2
network 172.16.0.0
no auto-summary
!
ip nat pool bluestudy 199.1.1.3 199.1.1.10 netmask 255.255.255.248
ip nat inside sourece list 2 pool bluestudy overload
ip nat inside sourece static 172.16.1.3 199.1.1.5
ip classless
ip route 0.0.0.0 0.0.0.0 srial0/0.1
ip http server
!
access-list 2 permit 172.16.1.0 0.0.0.255
access-list 101 permit ip 172.16.1.0 0.0.0.255 172.16.2.0 0.0.0.255(对方网络，只有到这个网络的信息包才加密)
snmp-server community public RO
!
line con 0
exec-timeout 0 0
password cisco
login
transport input none
line aux 0
line vty 0 4
password cisco
login
!
end