1. NSIS Mobility Reality Check Drafts talk about moving extensive state in the network between old and new routing path.  Excuse me but what state are we talking about here? Most today routers don’t maintain per node state or per flow state on intermediate routers. Primarily just on the access (first hop) router and firewalls/NAT boxes at border routers. Even future designs for stateful QoS don’t maintain per flow or per node state on most network nodes. RMD (draft-bader-rmd-qos-model-00.txt) specifies per Diffsrv queue state in interior nodes.

2. Some Possible Mobility-Related Problems* Mobile signals a firewall on access router for service access. Mobile signals a new border firewall/NAT box upon routing change. –But this isn’t any different than for a fixed host. Multi-interface mobile without Mobile IP hands over to new wireless medium, needs to signal middleboxes. *but these aren’t problems now and probably won’t be for quite a while

3. Keep in mind… The IETF works best on well defined problems which vendors and operators are motivated to solve. Without deployment or product pressure, research problems are difficult to impossible to come to consensus on.