Bulk Binding Update Support for Proxy Mobile IPv6

For extending the lifetime of a mobility session, the Proxy Mobile IPv6 specification requires the mobile access gateway to send a Proxy Binding Update message to the local mobility anchor on a per-session basis. In the absence of signaling semantics for performing operations with group-specific scope, this results in a significant amount of signaling traffic on a periodic basis between a given mobile access gateway and a local mobility anchor. This document defines optimizations to the binding update and revocation operations in Proxy Mobile IPv6 for performing operations with group-specific scope with the use of a group identifier.