Subject: I-D Action: draft-bormann-intarea-alfi-00.txt

From: [email-masked]
Date: Wed, 25 Apr 2012 08:50:02 -0700

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

	Title           : Adaptation Layer Fragmentation Indication
	Author(s)       : Carsten Bormann
	Filename        : draft-bormann-intarea-alfi-00.txt
	Pages           : 13
	Date            : 2012-04-25

   IPv6 defines a minimum MTU of 1280 bytes.  Many link layers are more
   limited in their choice of packet size.  Typically, IP adaptation
   layers for these link layers define a segmentation or fragmentation
   scheme to transport larger IP packets in multiple link layer packets.

   Often, adaption layer fragmentation schemes reduce some performance
   metric, such as the packet delivery rate.  Where application or
   transport protocols have a choice, it would therefore be desirable
   for them to know about any adaptation layer fragmentation that is
   going on, so they can choose packet sizes that minimize adaptation
   layer fragmentation.

   At the IP layer, fragmentation can be detected using a number of
   mechanisms used in Packetization Layer Path MTU Discovery [RFC4821].
   However, adaptation later fragmentation schemes are often designed to
   be "transparent", i.e. there is no way at higher layers to find out
   they had to be employed (except maybe by elaborate measurement
   schemes targeting one of the impacted performance metrics; this
   approach does not appear to be viable) [WEI].

   The present specification defines a mechanism for IPv6 adaptation
   layers to indicate the presence of adaptation layer fragmentation, as
   well as an indication of preferred packet sizes.

   The main objective of this version of the draft is to present a
   complete design in order to be able to gauge the complexity of the
   approach against the gains to be expected from implementing it.

   Comments are appreciated and should go to the [email-masked]
   mailing list.

A URL for this Internet-Draft is:
http://www.ietf.org/internet-drafts/draft-bormann-intarea-alfi-00.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-bormann-intarea-alfi-00.txt

The IETF datatracker page for this Internet-Draft is:
https://datatracker.ietf.org/doc/draft-bormann-intarea-alfi/