Comp 343-002/443-002, Online Computer Networks, Fall 2020

Peter Dordal, Loyola University Chicago Dept of Computer Science.

The text will be An Introduction to Computer Networks, second edition, written by myself and available for free online. Note that the book is updated regularly.

My general course groundrules are here. Exams will count for between 60% to 70% of your grade, with homework and programs making up the rest.

The midterm will be the week of October 12 and the final will be during the normal finals week.

My theory about online learning is that students learn best by working out hands-on examples; therefore the primary weekly activity will be reading assignments and then exercises based on that. There are some asynchronous lectures (most audio, some video). I will make myself available at least twice a week for synchronous meetings; I will also answer email and post on the Sakai discussion board. Students should try to participate in one of the synchronous sessions. The tentative schedule for these is as follows:
I will use Zoom. Length will be between 15 minutes to an hour, depending on demand.

While I will try to accept late homework, it is important for everyone to remain more-or-less together; this is not a "self-paced" course!

Most of the audio lectures are what I call mini-lectures, about twenty minutes in length. These are fast-paced, with the understanding that you can pause whenever you need to. I recommend listening to the lectures before reading the material.

Most of the course materials and assignments will be on Sakai.

Study Guides

These will be on Sakai.


Each week's assignment is generally due the Friday of the following week; eg September 6 for Week 1.

The schedule below is subject to change!

Homework can be submitted in .text, .odt, .doc/.docx, .xls/.xlsx, .rtf, etc. I discourage .pdf because I can't insert comments, but I will accept it. I will also accept image formats such as .jpeg (and for that matter .pdf images), but I recommend that you submit images only for those exercises for which you had to write out a diagram by hand. Some Mac formats I cannot accept simply because I cannot open them.

(As of August, the full assignment list is not ready yet.)

Chapter 1: Overview of Networks
Homework 1, due Fri Sept 4
Chapter 1, exercises  1.0, 2.0, 5.0, 6.0, 7.0, 8.0, 9.0
2.1   10-Mbps classic Ethernet
2.1.1 Ethernet Packet Format
2.1.2 Multicast
2.1.3 Ethernet Address Structure
2.1.4 LAN layer
2.1.5   Slot Time and Collisions
2.1.6   Exponential Backoff
2.2   100 Mbps (Fast) Ethernet
2.3   Gigabit Ethernet
2.4   Ethernet Switches and the learning algorithm
3.1   Spanning Tree Algorithm.
Homework 2, due Fri Sept 11
Chapter 2, exercises 1.0, 2.0, 5.0, 7.0

New exercise: use the diagram of exercise 3.0, but with the following transmissions instead:
  1. A sends to C
  2. C sends to A
  3. A sends to B
  4. B sends to D
Chapter 3, exercise 1.0
Chapter 4, Wireless:
4.1: Radio, 4.2: Wi-Fi (up through 4.2.4)
Chapter 5: 5.3
Chapter 6 (Links): 6.1
Chapter 7 (Packets): 7.1, 7.2, 7.3
Homework 3, due Fri Sept 18
Chapter 4: 1.0, 3.0
Chapter 5: 3.0(a)
Chapter 6: 1.0, 5.0
Chapter 7: 1.0, 2.0, 6.0, 8.0
Chapter 8: Sliding windows
Homework 4, due Fri Sept 25
Chapter 8: 3.0, 5.0, 6.0, 7.0, 8.0, 9.0, 12.0
Chapter 9: 9.1-9.7
(don't worry about numeric details of fragmentation)
Chapter 10: 10.1-10.4
Chapter 13: section 1: DV update algorithm
Homework 5, due Fri Oct 2
Chapter 9: 2.0, 3.0, 6.0, 8.0
Chapter 10: 1.0
Chapter 13: 2.0, 4.0
Chapter 16 (UDP): 16.1-16.3
Chapter 17 (TCP): 17.1-17.7
Homework 6, due Fri Oct 9
Chapter 13: 9.0, 11.0
Chapter 16: 4.0, 6.0, 7.0
Chapter 17: 2.0, 3.0, 4.0

No homework due Oct 16, because of the midterm




Java simpletalk examples

TCP: server, clientthreaded server
UDP: server, client


A viewer for the Internet: A galaxy-visualization tool is used to display all ISPs (as stars) and links between them.

Programming Projects

Summary of coverage, from An Introduction to Computer Networks

An Overview of Networks
Other LANs: Wi-Fi in particular
Links: briefly
Packets: briefly
Abstract Sliding Windows
IP version 4
IP version 6 (selections)
Routing Update Algorithms
Large-scale IP Routing
TCP Reno and Congestion Management
TCP Dynamics
Miscellaneous topics

Learning outcomes

Students will understand how the Internet is constructed, how LANs are built and managed, how data is routed to its destination, how connections are managed and implemented, how congestion is handled, and how security can be addressed.