Return-Path: william@bourbon.usc.edu Delivery-Date: Tue Dec 9 19:43:14 2008 X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on merlot.usc.edu X-Spam-Level: X-Spam-Status: No, score=-2.4 required=5.0 tests=AWL,BAYES_00 autolearn=ham version=3.2.3 Received: from bourbon.usc.edu (bourbon.usc.edu [128.125.9.75]) by merlot.usc.edu (8.14.1/8.14.1) with ESMTP id mBA3hEAX003702 for ; Tue, 9 Dec 2008 19:43:14 -0800 Received: from bourbon.usc.edu (localhost.localdomain [127.0.0.1]) by bourbon.usc.edu (8.14.2/8.14.1) with ESMTP id mBA3jgCF016844 for ; Tue, 9 Dec 2008 19:45:42 -0800 Message-Id: <200812100345.mBA3jgCF016844@bourbon.usc.edu> To: cs551@merlot.usc.edu Subject: Re: doubt about the DEC-bit scheme Date: Tue, 09 Dec 2008 19:45:42 -0800 From: Bill Cheng Someone wrote: > The DEC-bit scheme relies on the acknowledgement provided by the receiver to > the sender to convey information about congestion to the sender. However, > what about connectionless transport-layer protocols such as UDP that do no > provide any acknowledgement. It won't be able to use it. DEC-bit is a feedback mechanism. If there is no ACK, there would be no feedback. > In this context, is the DEC-bit scheme still fair to ALL users ? As I've mentioned in class, nothing is fair to all users because it's hard to even define "fair to all users"! -- Bill Cheng // bill.cheng@usc.edu