[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [RRG] Subnetwork Encapsulation and Adaptation Layer (SEAL)
The SEAL document has been updated again; this will be
the final version leading up to IETF71:
http://www.ietf.org/internet-drafts/draft-templin-seal-02.txt
SEAL in part specifies an MTU determination scheme based
on the Report Fragmentation (RF) concept that was first
proposed by Charles Lynn on the tcp-ip mailing list in
1987 and re-introduced by Steve Deering on the Path MTU
working group mailing list in 1989. Digests from those
lists are found at:
http://ipvlx.com/tcp_ip.txt
http://gatekeeper.dec.com/pub/DEC/WRL/mogul/mtudwg-log
Based on the list discussions, the Report Fragmentation
(RF) method seemed to be the most attractive approach
under consideration for IPv4 path MTU discovery, but was
abandoned in favor of the (Don't Fragment/Fragmentation
Needed) method that eventually became RFC1191. The RF
method seems to have been abandoned due in part to
difficulty in procuring an "RF" bit in the IPv4 header,
difficulty in defining an ICMP Fragmentation Report
message and the concern that not all hosts at that time
correctly implemented IP reassembly.
The SEAL proposal addresses all of these points (as well
as others) and shows that a Report Fragmentation-based
path MTU discovery capability for the Internet is still
possible and could correct the operational difficulties
associated with RFC1191 path MTU discovery. Moreover, the
SEAL approach supports true diversity, especially for
subnetworks that contain heterogeneous link types with
diverse MTUs and/or L2 address formats.
Please review and comment,
Fred
fred.l.templin@boeing.com
> -----Original Message-----
> From: Templin, Fred L
> Sent: Tuesday, February 12, 2008 5:07 PM
> To: rrg@psg.com
> Subject: RE: [RRG] Subnetwork Encapsulation and Adaptation
> Layer (SEAL)
>
> An update to this document has been posted:
>
> http://www.ietf.org/internet-drafts/draft-templin-seal-01.txt
>
> Please use this version as the basis for further
> review and discussion.
>
> Fred
> fred.l.templin@boeing.com
>
> > -----Original Message-----
> > From: Templin, Fred L
> > Sent: Monday, February 11, 2008 4:16 PM
> > To: rrg@psg.com
> > Subject: [RRG] Subnetwork Encapsulation and Adaptation Layer (SEAL)
> >
> > Attached please find a new draft that proposes a
> > "Subnetwork Encapsulation and Adaptation Layer (SEAL)".
> > This work goes a step beyond the sprite-mtu proposal, and
> > addresses the tunnel MTU determination and duplicate packet
> > detection problem spaces such as required for LISP, MANET,
> > etc. But, it also draws on some profound concepts that
> > were first proposed by others many years ago. (Please see
> > Appendix A for an historical account and correct anything
> > I may have mis-characterized.)
> >
> > From a bigger picture, the proposal provides a generalized
> > abstraction for the carriage of IP over any subnetwork that
> > connects routers, e.g., Mobile Ad-hoc Networks, enterprise
> > networks, the interdomain routing core, etc. The proposal
> > is particularly applicable for subnetworks that include
> > links with diverse MTUs and L2 address formats, as well
> > as for subnetworks that may incur packet duplication due
> > to temporal routing loops, flooding, etc.
> >
> > Please review and provide comments,
> >
> > Fred
> > fred.l.templin@boeing.com
> >
> > -----Original Message-----
> > From: Internet-Drafts@ietf.org [mailto:Internet-Drafts@ietf.org]
> > Sent: Monday, February 11, 2008 3:30 PM
> > To: i-d-announce@ietf.org
> > Subject: I-D Action:draft-templin-seal-00.txt
> >
> > A New Internet-Draft is available from the on-line Internet-Drafts
> > directories.
> >
> > Title : Subnetwork Encapsulation and Adaptation Layer
> > Author(s) : F. Templin
> > Filename : draft-templin-seal-00.txt
> > Pages : 18
> > Date : 2008-02-11
> >
> > Subnetworks connect routers within a bounded region, and may also
> > connect to other networks including the Internet. These routers
> > forward unicast and multicast packets over paths that span multiple
> > IP- and/or sub-IP layer forwarding hops which may configure diverse
> > Maximum Transmission Units (MTUs) and introduce packet duplication.
> > This document specifies a Subnetwork Encapsulation and Adaptation
> > Layer (SEAL) that supports simplified duplicate packet detection and
> > accommodates links with diverse MTUs.
> >
> > A URL for this Internet-Draft is:
> > http://www.ietf.org/internet-drafts/draft-templin-seal-00.txt
> >
> > To remove yourself from the I-D Announcement list, send a message to
> > i-d-announce-request@ietf.org with the word unsubscribe in
> > the body of
> > the message.
> > You can also visit
> https://www1.ietf.org/mailman/listinfo/I-D-announce
> > to change your subscription settings.
> >
> > Internet-Drafts are also available by anonymous FTP. Login with the
> > username "anonymous" and a password of your e-mail address. After
> > logging in, type "cd internet-drafts" and then
> > "get draft-templin-seal-00.txt".
> >
> > A list of Internet-Drafts directories can be found in
> > http://www.ietf.org/shadow.html
> > or ftp://ftp.ietf.org/ietf/1shadow-sites.txt
> >
> > Internet-Drafts can also be obtained by e-mail.
> >
> > Send a message to:
> > mailserv@ietf.org.
> > In the body type:
> > "FILE /internet-drafts/draft-templin-seal-00.txt".
> >
> > NOTE: The mail server at ietf.org can return the document in
> > MIME-encoded form by using the "mpack" utility. To use this
> > feature, insert the command "ENCODING mime" before the "FILE"
> > command. To decode the response(s), you will need "munpack" or
> > a MIME-compliant mail reader. Different MIME-compliant mail
> > readers
> > exhibit different behavior, especially when dealing with
> > "multipart" MIME messages (i.e. documents which have been split
> > up into multiple messages), so check your local documentation on
> > how to manipulate these messages.
> >
> > Below is the data which will enable a MIME compliant mail reader
> > implementation to automatically retrieve the ASCII version of the
> > Internet-Draft.
> >
>
> --
> to unsubscribe send a message to rrg-request@psg.com with the
> word 'unsubscribe' in a single line as the message text body.
> archive: <http://psg.com/lists/rrg/> & ftp://psg.com/pub/lists/rrg
>
--
to unsubscribe send a message to rrg-request@psg.com with the
word 'unsubscribe' in a single line as the message text body.
archive: <http://psg.com/lists/rrg/> & ftp://psg.com/pub/lists/rrg