Computer Science 455/555
Intro to Networks and Communications
Dr. Michele Weigle     Fall 2006     TA: Rabia Haq
mweigle at     MWF, 11-11:50am     rhaq at
E&CS 3214     Hughes 1117     E&CS 3100
Office Hours: MW 2-3pm or by appointment           683-4652
Office Hours: TR 2-3pm

Old Announcements

Wed, Nov 08 @ 10:12 am - Solution to Program 3
I've put up a sample solution to Program 3 on Blackboard under Course Documents. This is just for the purpose of giving you a solution and should not be distributed to other students.

Wed, Nov 08 @ 9:12 am - Prog 3 Tests
The URLs used to test your Program 3 submissions have been posted

Mon, Nov 06 @ 12:24 pm - Paper 1 Due Date
I've changed the due date for Paper 1 to next Monday, Nov 13 (before class).

Thu, Nov 02 @ 3:48 pm - Prog 3
Turn in Program 3 by Monday (Nov 6) in order to get any credit for the assignment.

Mon, Oct 30 @ 9:56 am - Friday's Assignments
Make sure to check the schedule for Friday, Oct 27 for assignments of Homework 3, Paper 1, and the final project/paper.

Mon, Oct 30 @ 9:55 am - Paper 1
I've posted PDF versions of both papers on Blackboard under Course Documents.

Thu, Oct 26 @ 3:31 pm - Program 3 Questions

Mon, Oct 23 @ 10:02 am - String References
I've added a couple links under Useful Links to C and C++ string reference pages. Remember that to use the C string functions, you need to include string.h.

Fri, Oct 20 @ 3:32 pm - Intro to ns-2
Next Friday's (Oct 27) lecture on the ns-2 network simulator is optional for CS 455. You must still submit your writeup for Program 3 before the start of class - submission via Blackboard is fine.

Wed, Oct 18 @ 3:01 pm - TCP Intro
Take a look at sections 1.1.3-1.3 (pgs. 4-18) of this TCP Intro that I mentioned in class Weds. I'll also post this below under Useful Links.

Wed, Oct 18 @ 10:12 am - MidTerm Grades Posted
I've posted your mid-term grades on Blackboard. You will see "MidTerm", which is your grade on the mid-term exam and "Current Avg", which is your average so far in the course. Exams will be returned once all makeup exams have been taken.

Mon, Oct 16 @ 2:36 pm - Go-Back-N Performance
Take a look at this slide that could take the place of slide 30 in the lecture notes from today. We'll look at this on Wednesday.

Fri, Oct 13 @ 9:54 am - Program 3 Assigned
Program 3 has been assigned and will be due in two weeks on Fri, Oct 27. Start early. No extensions will be given.

Wed, Oct 11 @ 9:39 am - Mid-Term Exam and Grades
The mid-term exam is this Friday, Oct 13. Please get to class on time! Your grades for Homework 2 and your current average going into the mid-term have been posted on Blackboard. The mid-term will be graded and your grades will be posted before the final drop date (Oct 24).

Fri, Oct 6 @ 9:57 am - Mid-Term Study Guide

Thu, Oct 5 @ 11:12 am - Program 2 Tests
The test cases we used for Program 2 have been posted here. We adapted these tests according to the format displayed by your client.

Wed, Oct 4 @ 2:04 pm - Homework 2 Clarifications
Review question 10: Assume the year is 2006 and the number of seconds is 05.
Problem 1: Make sure that you include transmission delay in your answer.
Problem 1: Assume that "2 hops" means that there are 2 links (1 router) in between your client and server.
Problem 4: Give the server contacted (ex: .com nameserver) and what information was obtained from that server (ex: IP address of nameserver).

Fri, Sep 29 @ 12:10 pm - Homework 2 Assigned
Homework 2 has been assigned, and is due next Friday, Oct 6.

Wed, Sep 27 @ 4:04 pm - Replacement HTTP Slides
Please see the course schedule for replacement slides for slides 39-42 for the HTTP lecture. We'll go over these on Friday.

Mon, Sep 25 @ 11:53 am - Program 2 Postponed
The new due date for Program 2 is Friday, Sep 29 before class. Let me or Rabia know if you want us to clear your current submission.

Sat, Sep 23 @ 7:28 pm - Program 2 Questions

Mon, Sep 18 @ 10:48 am - Office Hours Weds
This week only, my office hours on Weds will be from 12:45-1:45pm.

Mon, Sep 18 @ 9:51 am - Sample TCP and UDP Code
I've updated the TCP and UDP client and server code to reflect the changes I mentioned in class Friday. Basically the only things different are the addition of ntohs around sin_port when it's printed and adding bzero to make sure the buffer is clear before receiving a message. This code is linked from the schedule. Make sure that you reload the page to get the latest version -- it should have today's date on the 2nd line.

Thu, Sep 14 @ 12:08 pm - Test Cases for Program 1
I've posted the test cases used for grading Program 1 and their correct output.

Thu, Sep 14 @ 10:10 am - Code Examples for Sep 15
The latest versions of the code examples were posted yesterday at 1:45pm. Please print the new versions and bring them to class tomorrow.

Wed, Sep 13 @ 12:04 pm - Honor Code Procedures
The complete rules and procedures for Honor Code violations are available in the University Catalog pgs. 16-18. This is available online through the Office of Academic Affairs. Every student is responsible for knowing the rules and consequences.

Fri, Sep 8 @ 10:31 am - Instructions for Submitting Assignments
I've posted a web version of the instructions for submitting assignments via Blackboard under Useful Links.

Wed, Sep 6 @ 2:06 pm - New Honor Policy for Written Homework
You may talk about the written homework problems with other students, but each student must write up the solutions in their own words. You must include the names of the students you worked with in your homework submission. Since the exam questions will be similar in style to the written homework, it is your responsibility to make sure that you understand how to answer each question on your own. This policy does not extend to programming assignments, which must be completed on your own.

Wed, Sep 6 @ 9:42 am - Rabia's New Office
Please note that Rabia's office has changed to E&CS 3100 and her office phone number to 683-4652.

Tue, Sep 5 @ 9:38 am - ACM Meeting
The first ACM meeting of the year will be Tuesday, Sep 5 at 12:20pm in the E&CS first floor auditorium. Lunch will be served (free to non-members) and there will be free giveaways. For more info see

Fri, Sep 1 @ 7:00 am - University Closed
Classes have been cancelled for today due to TS Ernesto.

Wed, Aug 30 @ 12:03 pm - Prog 1
Program 1 has been assigned. It's due next Wed and can be found from the course schedule or through Blackboard Assignments.

Tue, Aug 29 @ 10:42 am - Class Pictures
I've posted the pictures I took on Monday on our Blackboard site under Course Documents. Due to my impressive camera skills, some of the pictures turned out blurry. =) I'll bring the camera on Weds if you'd like me to re-take your picture, or you can email me a picture.

Mon, Aug 28 @ 3:17 pm - TA Info
Rabia Haq will be the TA for this class. She will be available to answer questions by email and will hold office hours (TBA). Please put "CS 455" or "CS 555" in the subject line of emails sent to her.

Thu, Aug 24 @ 4:12 pm - Syllabus Posted
The course syllabus has been posted as well as the slides we'll use on the first day of class. See the schedule.

Fri, Aug 4 @ 11:18 am - Welcome!
Welcome to the CS 455/555 webpage. I'll be adding more information soon.