From: Jonathan Morton <chromatix99@gmail.com>
To: Fred Baker <fred@cisco.com>
Cc: bloat@lists.bufferbloat.net
Subject: Re: [Bloat] Random idea in reaction to all the discussion of TCP flavours - timestamps?
Date: Thu, 17 Mar 2011 01:23:11 +0200 [thread overview]
Message-ID: <9DB38C10-12C6-4B08-B038-16B9437FAE57@gmail.com> (raw)
In-Reply-To: <0D064802-2668-4FB7-A0BB-8F717DD4CAF8@cisco.com>
On 17 Mar, 2011, at 12:48 am, Fred Baker wrote:
>> This reminds me of a related concept, using the TTL really as 'Time To Live' (in today's IP, it's more of a 'Remaining Hop Count). According to RfC 791, a router that buffers a packet by n seconds must decrease its TTL by n. I doubt that many routers implement this properly.
>
> There is, of course, a fundamental bug in that, noted in RFC 970.
>
> RFC 1812, which I edited, contains this text (that I didn't write):
>
> In this specification, we have reluctantly decided to follow the
> strong belief among the router vendors that the time limit
> function should be optional.
The major problem with the original TTL spec was that a router generally doesn't keep a packet for an integer number of seconds (at least, not in anything but the most ancient of hardware). If three separate routers each buffer for 350ms, that's about 1 second elapsed, but there is no way for the routers to indicate this to each other. Yet the TTL field was an integer number of seconds.
The later hop-count spec is much saner.
- Jonathan
next prev parent reply other threads:[~2011-03-16 23:23 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-03-15 10:36 Jim Gettys
2011-03-15 14:40 ` Jim Gettys
2011-03-15 16:47 ` Jonathan Morton
2011-03-15 17:59 ` Don Marti
2011-03-15 18:14 ` Rick Jones
2011-03-15 18:31 ` John W. Linville
2011-03-15 19:40 ` Jonathan Morton
2011-03-15 19:59 ` Rick Jones
2011-03-15 20:51 ` John W. Linville
2011-03-15 21:31 ` Rick Jones
2011-03-16 0:32 ` John W. Linville
2011-03-16 1:02 ` Rick Jones
2011-03-15 22:01 ` Jonathan Morton
2011-03-15 22:19 ` Stephen Hemminger
2011-03-15 22:26 ` Jonathan Morton
2011-03-15 22:36 ` Rick Jones
2011-03-15 22:40 ` Jonathan Morton
2011-03-15 22:42 ` Stephen Hemminger
2011-03-15 22:52 ` Eric Dumazet
2011-03-15 23:02 ` Rick Jones
2011-03-15 23:12 ` Jonathan Morton
2011-03-15 23:25 ` Rick Jones
2011-03-15 23:33 ` Jonathan Morton
2011-03-15 23:46 ` Dave Täht
2011-03-16 0:49 ` Jonathan Morton
2011-03-16 1:02 ` Dave Täht
2011-03-16 1:28 ` Jonathan Morton
2011-03-16 1:59 ` Dave Täht
2011-03-16 2:23 ` Jonathan Morton
2011-03-16 22:22 ` [Bloat] Random idea in reaction to all the discussion of TCPflavours " Richard Scheffenegger
2011-03-16 23:38 ` richard
2011-03-16 23:50 ` Rick Jones
2011-03-17 12:05 ` Fred Baker
2011-03-17 12:18 ` Fred Baker
2011-03-17 17:27 ` Dave Täht
2011-03-18 18:30 ` Richard Scheffenegger
2011-03-18 18:49 ` Fred Baker
2011-03-20 11:40 ` Jonathan Morton
2011-03-20 22:18 ` david
2011-03-20 22:45 ` Jonathan Morton
2011-03-20 22:50 ` Dave Täht
2011-03-20 22:55 ` grenville armitage
2011-03-20 23:04 ` Dave Täht
2011-03-20 23:14 ` Jonathan Morton
2011-03-20 23:19 ` Dave Täht
2011-03-20 23:23 ` Dave Täht
2011-03-20 22:58 ` Jonathan Morton
2011-03-21 1:28 ` david
2011-03-21 1:56 ` Wesley Eddy
2011-03-18 18:27 ` [Bloat] Random idea in reaction to all the discussion ofTCPflavours " Richard Scheffenegger
2011-03-16 22:07 ` [Bloat] Random idea in reaction to all the discussion of TCPflavours " Richard Scheffenegger
2011-03-17 0:10 ` Jonathan Morton
2011-03-16 0:47 ` [Bloat] Random idea in reaction to all the discussion of TCP flavours " John W. Linville
2011-03-16 20:07 ` Jim Gettys
2011-03-17 2:26 ` Jonathan Morton
2011-03-17 18:22 ` Rick Jones
2011-03-17 21:50 ` Jonathan Morton
2011-03-17 22:20 ` Rick Jones
2011-03-17 22:56 ` Jonathan Morton
2011-03-18 1:36 ` Justin McCann
2011-03-18 5:51 ` Eric Dumazet
2011-03-15 16:34 ` Jonathan Morton
2011-03-15 18:13 ` Stephen Hemminger
2011-03-16 5:41 ` Fred Baker
2011-03-16 6:26 ` Jonathan Morton
2011-03-16 8:55 ` [Bloat] Random idea in reaction to all the discussion of TCPflavours " Richard Scheffenegger
2011-03-16 9:04 ` [Bloat] Random idea in reaction to all the discussion of TCP flavours " BeckW
2011-03-16 22:48 ` Fred Baker
2011-03-16 23:23 ` Jonathan Morton [this message]
2011-03-17 8:34 ` BeckW
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