Return-Path: william@bourbon.usc.edu Delivery-Date: Mon Oct 13 21:24:06 2008 X-Spam-Checker-Version: SpamAssassin 3.2.3 (2007-08-08) on merlot.usc.edu X-Spam-Level: X-Spam-Status: No, score=-2.3 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 m9E4O6J0011319 for ; Mon, 13 Oct 2008 21:24:06 -0700 Received: from bourbon.usc.edu (localhost.localdomain [127.0.0.1]) by bourbon.usc.edu (8.14.2/8.14.1) with ESMTP id m9E4Vg7n002171 for ; Mon, 13 Oct 2008 21:31:42 -0700 Message-Id: <200810140431.m9E4Vg7n002171@bourbon.usc.edu> To: cs551@merlot.usc.edu Subject: Re: hello msg Date: Mon, 13 Oct 2008 21:31:42 -0700 From: Bill Cheng Someone wrote: > the spec says - "Please note that neighbor is a bi-directional > relationship. Therefore, when node B gets a hello message from node A, > and node A is not currently node B's neighbor, node B should send a > hello message to node A" > > Since there is no concept of 'init_neighbor_list' for a beacon node, > when a beacon node say X sends "hello" to another beacon node say Y, Y > knows it is connecting to a beacon node, then why does it need to send > a 'hello' message back. the grading guidelines mention 2 hello > messages be exchanged for every beacon-to-beacon connect. Actually, you've got a point! If X initiates a connection to Y, only X needs to tell Y who X is. So, only one HELLO message from X to Y is necessary. But since the spec says that our protocol requires that you must exchange HELLO messages, you need to do it because it's a bit late to change the protocol now! So, please exchange HELLO messages. Thanks! -- Bill Cheng // bill.cheng@usc.edu