Cisco router VPN configuration statement

The VPN configuration of the Cisco router is not important for network security, but also makes the user more convenient during use. In this experiment, we use the Cisco 2600 router and the Cisco router VPN configuration to implement the blue campus. The networks between the first branch and the second branch are interconnected. In order to be close to practicality, the ISP is still simulated through the Cisco 3640 in the middle. Through the introduction in the basic part of the network, you should have a certain understanding of the VPN routing technology, there are two main aspects in the implementation of VPN: the topology of VPN Tunnel and IPSec Encryption is as follows:

 
 

  
  
Cisco 2600 with GRE Tunnel   
  
  
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  
  
  
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  
  
  
login  
  
  
!  
  
  
end  
 
 

The above is a comprehensive summary of the Cisco router VPN configuration statement. I hope you will have a deeper understanding of the Cisco router VPN configuration after reading it, to ensure our network security.