The IP over ATM Mailing List Archive by date

[jhalpern@newbridge.com (Joel Halpern)]

Jon asks for some interesting possible services/packets/... for
operation over ATM.  In doing so, he suggests and explicit congestion
bit for the operation of TCP/IP on AAL5/ABR.

While I sympathise with the request, I am not sure, particularly in an
explicit rate scheme, what it means.  Given that one is periodically
getting allocations of bandwidth, what is the indication that some
change in allocation should be considered "congestion"?  Any decrease
in ones allocated rate?  A decrease of 50%?  Or something else.  In
some sense the system is designed to operate in an environment that is
always partially congested.  THe whole point of the system is to keep
the operation away from the knee of the behavioral curve where congestive
collapse occurs.  So what point along the allowed region is "congestion"?

Yours,
Joel M. Halpern				jhalpern@newbridge.com
Newbridge Networks Inc.