At 11:16 AM 03/09/2000 -0600, Schipper, Dell wrote:
>I recall that Larry Roberts a few years ago gave presentations (at
>NetWorld+InterOp ?) that compared the congestion avoidance algorithms of
>ATM-ABR service to TCP/IP. I know he has started a new company since
>then and I do not have any contact information.
One of my favorites along those lines was:
"End-to-End Traffic Management Issues in IP/ATM Internetworks,"
draft-jagan-e2e-traf-mgmt-00.txt, S. Jagannath and N. Yin,
August 1997.
- paul
[snip]
Abstract
This document addresses the end-to-end traffic management issues in
IP/ATM internetworks. In the internetwork environment, the ATM
control mechanisms (e.g., Available Bit Rate (ABR) and UBR with Early
Packet Discard (EPD)) are applicable to the ATM subnetwork, while the
TCP flow control extends from end to end. We investigated the end to
end performance in terms of TCP throughput and file transfer delay in
cases using ABR and UBR in the ATM subnetwork. In this document, we
also discuss the issue of trade-off between the buffer requirements
at the ATM edge device (e.g., Ethernet-ATM switch, ATM router
interface) versus ATM switches inside the ATM network.
Our simulation results show that in certain scenarios (e.g., with
limited edge device buffer memory) UBR with EPD may perform
comparably to ABR or even outperform ABR. We show that it is not
sufficient to have a lossless ATM subnetwork from the end-to-end
performance point of view. The results illustrate the necessity for
an edge device congestion handling mechanism that can couple the ABR
and TCP feedback control loops. We present an algorithm that makes
use of the ABR feedback information and edge device congestion state
to make packet dropping decisions at the edge of the ATM network.
Using the algorithm at the edge device, the end-to-end performance in
throughput and delay are improved while using ABR as the ATM
subnetwork technology and with small buffers in the edge device.
[snip]
