Return-Path: william@bourbon.usc.edu Delivery-Date: Thu Dec 11 12:19:48 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 mBBKJmdh029385 for ; Thu, 11 Dec 2008 12:19:48 -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 mBBKMKAb031213 for ; Thu, 11 Dec 2008 12:22:20 -0800 Message-Id: <200812112022.mBBKMKAb031213@bourbon.usc.edu> To: cs551@merlot.usc.edu Subject: Re: Regarding Extra homework problem 4 Date: Thu, 11 Dec 2008 12:22:20 -0800 From: Bill Cheng Someone wrote: > Extra homework problem# 4 says" > > (1) * Assuming that the bucket is initially full*, what bucket depth > does the flow need for a token rate of 2 packets per second? > > (2) Assuming that the bucket is initially full, what bucket depth > does the flow need for a token rate of 4 packets per second? > > But the solution says: > Let's pretend the bucket volume can be negative. We will have the > following situation *if we start with an empty bucket (bucket volume = 0): * > > It creates a confusion about what should be the initial bucket condition. It's just a trick to solve the problem! I'm not sure what you are asking. -- Bill Cheng // bill.cheng@usc.edu