Re: [FE] Frame size poll
Kevin-
The belief that I have that I would put forth for testing would point to
#3.
The theory behind this is that the number should be some small number of
bytes less than 2048 (2^10). That implementations have been built with a
2048 buffer allocation per packet. Further, that included in that
allocation is some requirement for tagging inside a switch to indicate
(for example) things such as length, source port, destination port,
priority, etc.
IF my theory is valid THEN my number would be:
(2048)
minus (MAX reasonable internal processing tag size)
My GUESS at that tag size would be something like 12 bytes which would
yield a resultant number
of: 2036
The above number is open to negotiation or invalidation. Negotiation
would be on the basis of actual implementation experience. I am
personally untainted. Invalidation would be that everybody says my theory
of implementation is all wet.
(My hope is that, should my theory and number turn out to be correct, our
rationale would understood and well accepted and not subject to the sorts
of derision directed at ATM for its 53 byte decision.)
Hopefully this will be adequate meat to kick off the discussion.
Best regards,
Geoff
At 12:11 PM 9/2/2004 -0700, Kevin Daines wrote:
Now to the poll. Would you prefer:
1) 1875 (which is based on the repeater calculation)
2) 2048 (a power of 2)
3) some other number (please specify)
Kevin Daines
Chair, 802.3 Frame Expansion Study Group