http://www.rfc-editor.org/rfc/rfc1981.txt
RFC 1981: Path MTU Discovery for IP version 6, J. McCann, S. Deering, J. Mogul1996-08-01T23:00:00-00:00This document describes Path MTU Discovery for IP version 6. It is largely derived from RFC 1191, which describes Path MTU Discovery for IP version 4. [STANDARDS-TRACK]