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Re: Questions about Internet Packet Losses

  • From: Howard C. Berkowitz
  • Date: Tue Jan 14 05:58:47 1997 
Tony,

Thanks for posting some useful raw data.  A clarification -- in some
messages, you say you've stripped headers, but is unclear if you did so in
your top 10 table.

If so, 41 sounds reasonable for noncompressed-header Telnet, with the 44,
52, 48, 56, etc., sizes, as a guess, to a rounded-up transmission buffer.
44 in implementation where memory is allocated/managed in 4 byte quanta, 52
in 8 byte quanta, etc.

Silly question, at 5AM...MSS is one of those acronyms I use for its own
convenience and beauty, without really stopping to think what it stands
for...Mean Segment Size?
>
>Unanswered questions for further research:
>1) What in hell is sending so many 40 byte packets?  Are we really seeing
>   productive ACKs?  Or is it just HTTP bogosity?  This really sucks.
>2) What OS is using a 512 MSS?  256?
>3) What are the minimal revs of various BSD flavors to exceed the 576 MTU
>   by default?
>4) 41 bytes is pretty obviously interactive traffic.  Is the intuition
>   correct?  What's so special about 44, 52, 48 and 56?  What do people do
>   with 4, 8, 12 and 16 bytes of data?  And why not any of the odd values?
>
>Tony
>
>		Tony's Top 10
>Packet Size	Percentage
>40		44.838		"ACKs, SYNs, FINs, RSTs "
>552		9.19		512 MSS
>1500		6.839		Happy boxes
>576		5.779		BSD bogosity
>44		4.719		??
>52		1.175		??
>48		0.884		??
>41		0.776		??
>56		0.73		??
>296		0.717		256 MSS



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