Cisco IOS Cookbook, 2nd Edition

Local Area Mobility

Problem

You want to set up Local Area Mobility to allow devices to roam throughout your network.

Solution

In this example, the roaming device will have a statically configured address in the 192.168.10.0/24 range. We have to configure the home router to use Proxy ARP for mobile nodes, allowing other locally connected devices in the same range to communicate transparently with the roaming device:

RouterHome#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RouterHome(config)#interface FastEthernet0/0
RouterHome(config-if)#ip address 192.168.10.1 255.255.255.0
RouterHome(config-if)#ip proxy-arp
RouterHome(config-if)#ip mobile arp
RouterHome(config-if)#exit
RouterHome(config)#router eigrp 99
RouterHome(config-router)#network 192.168.10.0
RouterHome(config-router)#default-metric 10000 10 255 1 1500
RouterHome(config-router)#redistribute mobile
RouterHome(config-router)#no auto-summary
RouterHome(config-router)#exit
RouterHome(config)#end
RouterHome#

Then we have to configure the foreign router, which supports the network segment where our roaming node temporarily finds itself:

RouterForeign#configure terminal
Enter configuration commands, one per line.  End with CNTL/Z.
RouterForeign(config)#interface FastEthernet0/0
RouterForeign(config-if)#ip address 192.168.110.1 255.255.255.0
RouterForeign(config-if)#ip proxy-arp
RouterForeign(config-if)#ip mobile arp
RouterForeign(config-if)#exit
RouterForeign(config)#router eigrp 99 RouterForeign(config-router)# ...