[6935] in North American Network Operators' Group
Re: Questions about Internet Packet Losses
daemon@ATHENA.MIT.EDU (Tony Li)
Mon Jan 13 23:28:08 1997
Date: Mon, 13 Jan 1997 20:24:46 -0800 (PST)
From: Tony Li <tli@jnx.com>
To: vern@ee.lbl.gov
CC: avg@pluris.com, nanog@merit.edu
In-reply-to: <199701140333.TAA23212@daffy.ee.lbl.gov> (message from Vern
Paxson on Mon, 13 Jan 1997 19:33:49 PST)
I believe you're misinterpreting the numbers. The raw data for those
numbers (if they're the same ones I'm thinking of)
I doubt it, it's relatively new data. Like last Thursday. ;-)
indicate that 9% of the packets had a 512 byte *payload*.
I already subtracted off the 40 bytes for the headers. I meant MSS.
You're correct, of course, that the percentage of packets at that size does
not directly reflect the percentage of hosts with that as an MSS. However,
the spikes in the packet percentages are clearly due to hosts using that
MSS. You would otherwise expect to see a "smooth" distribution across
packet sizes, which is not at ALL what's happening.
One of my main findings is that independently-written (i.e.,
non-BSD-derived) TCP's are much more likely to have serious performance
and congestion problems.
Wow. Imagine that. ;-)
Tony
