Thanks for your comments.
These are good questions.
The feature that I am talking about is an IOS router feature, not a wireless AP or controller feature. You are correct, the 44xx controllers really don't have the true Cisco IOS that runs on routers and switches.
The Cisco IOS Mobile IP feature that I am talking about would run on routers. This feature would allow a client to have a STATIC IP address and move from subnet to subnet without having to renegotiate an IP address, subnet mask, and default gateway using DHCP. Now, as far as the wireless AP associations, this feature has nothing to do with that. The AP's running WDS may be able to allow seamless associations (and wireless roaming) between AP's but, as I understand it, that doesn't take care of the IP addressing. With WDS and seamless roaming between AP's, you would stay on the same IP subnet. Many people put all their AP's on the same subnet so that you don't have to renegotiatie DHCP but, in a large campus, that may not always be possible.
There are so many different facets to Mobile IP. What I described is a Cisco IOS Router feature. Cisco also has Mobile Networks that allow ROUTERS to roam across the network. Then they have The Cisco Mobile client that is Mobile IP software that runs on a Windows workstation.
I appreciate your comments and good questions.
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