IP modifications for ATM

[Tony Zaide <[e-mail]>]

Hello everyone

My intent is not to fuel another debate, but simply for my own
understanding.   I have posed the following question at the ATM Year '96
but did not obtain a clear answer:

With all the work that has been proposed to modify the IP protocol suite
(i.e., RSVP MARS, .... etc) to give QoS and signalling capabilities among
others, has there been any thought to let IP know the concept of virtual
circuits?

In other words, can the IP hardware interface drivers be modified such it
can recognize the presence of either an ATM-based underlying network
(NMBA), or a LAN-based network (CSMA/CD, TR, ... ).  If it sees an
ATM-based network,  then it sends the traffic at a VC rate, rather than at
the link speed.
The purpose would be to increase the throughput of IP over ATM traffic
not to provide QoS, since sending traffic at VC rate might decrease the
probability of packet discards at the relatively smaller ingress buffers on
the ATM switch, thus decreasing re-transmitts.

Rgs,
Tony

>>> Albert Manfredi <[e-mail]> 05/06/96 
-  02:13pm >>>
The reason why ATM seems to be receiving so much bad press lately
with respect to carrying IP (and in many circles, carrying IP is seen as
being critical to its survival), is that IP over ATM is perceived as being
hopelessly complicated. In my opinion, one reason for this state of affairs
is that IP over ATM proposals are invariably IP over generic
NBMA net proposals. So ATM's assets must always be discounted or
ignored, and ATM ends up being a liability every time, compared with
broadcast LANs. And, of course, all the cases that have to be covered
result in complicated header formats.