Hi, In section 4.2 of RFC 2461 regarding the RA message format the following is mentioned
Reserved A 6-bit unused field. It MUST be initialized to zero by the sender and MUST be ignored by the receiver. The mobile-ipv6 draft draft-ietf-mobileip-ipv6-24.txt mandates using the most significant bit of this field as a home agent bit(will be set to 1 if the router is also a MIPv6 HA on this link). I do not know what is the best way to solve this apparent contradiction. I see the following possible solutions (in no particular order) * Reduce the reserved field length in RFC2461bis to 5 bits * Change the MUSTs to SHOULDs in RFC2461bis * Put a note on RFC2461/RFC2461bis in the rfc-index saying it has been updated by the MIPv6 RFC(when it comes out) Regards Suresh -------------------------------------------------------------------- IETF IPv6 working group mailing list [EMAIL PROTECTED] Administrative Requests: https://www1.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------