Subject: I-D Action: draft-generic-v6ops-tunmtu-01.txt

From: [email-masked]
Date: Thu, 24 May 2012 10:54:18 -0700

A New Internet-Draft is available from the on-line Internet-Drafts directories.

	Title           : Generic Tunnel MTU Determination
	Author(s)       : Fred L. Templin
	Filename        : draft-generic-v6ops-tunmtu-01.txt
	Pages           : 8
	Date            : 2012-05-24

   The tunnel MTU for popular IP-in-IP tunneling mechanisms is currently
   recommended to be set to 1500 (or less) minus the length of the
   encapsulation headers when static MTU determination is used.  This is
   to avoid IP fragmentation within the tunnel, but requires the tunnel
   ingress to either fragment any IP packet larger than the MTU or drop
   the packet and return an ICMP Packet Too Big (PTB) message.  Concerns
   for operational issues with both IPv4 and IPv6 Path MTU Discovery
   point to the possibility of MTU-related black holes when a packet is
   dropped due to an MTU restriction.  Fortunately, the "Internet cell
   size" is 1500 bytes, i.e., the minimum MTU configured by the vast
   majority of links in the Internet.  We also note that these same
   considerations apply to the encapsulation of any combination of IP-
   within-IP protocol versions.  This document therefore presents a
   method to boost the tunnel MTU to larger values.

A URL for this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-generic-v6ops-tunmtu-01.txt

Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/

This Internet-Draft can be retrieved at:
ftp://ftp.ietf.org/internet-drafts/draft-generic-v6ops-tunmtu-01.txt

The IETF datatracker page for this Internet-Draft is:
https://datatracker.ietf.org/doc/draft-generic-v6ops-tunmtu/