Subject: [nemo] Legacy MIPv6 HAs - Issue 15

From: Vijay Devarapalli <[email-masked]>
Date: Fri, 26 Sep 2003 11:17:35 -0700

hi all,

when a legacy MIPv6 HA (with no Mobile Router support) 
receives a BU with the Mobile Router flag set, it just 
ignores the flag. it also ignores any mobility options that 
it does not understand. therefore the mobility options 
introduced by Nemo will be ignored. the legacy HA will just 
process the BU and return 0 (Binding Update accepted) in the 
BAck. the Mobile Router does not know that the HA didn't setup 
forwarding for the Mobile Network.

this issue was discussed in the design team. the discussion 
is at http://people.nokia.net/vijayd/nemo/issue15.txt.

a proposal to resolve this:

introduce a new Binding Ack status value that indicates success
for a Binding Update from a Mobile Router. so we will have the
following success status values.

           0 Binding Update accepted

           1 Accepted but prefix discovery necessary

           2 Mobile Router Binding Update accepted

legacy MIPv6 HAs will return 0. Nemo HAs will return 2.

status values 0 and 1 are defined in the MIPv6 spec. 2 will
be defined in the Nemo basic support draft.

comments?

Vijay