A Larger Internet Key Exchange version 2 (IKEv2) Payload

The messages of the Internet Key Exchange version 2 (IKEv2) protocol are made up of payloads. The current protocol limits each of these payloads to 64KB by having a 2-byte length field. While this is usually enough, several of the payloads may need to be larger. This document updates RFC 7296 by defining an extension that allows larger payloads.