Welcome to the home page for ECE2305 "Introduction to Communications and Networking" for D-term 2014.

announcements and lecture slides

[02-May-2014] A nice summary on link-state versus distance vector routing.
[02-May-2014] Some slides on routing.
[29-Apr-2014] Some slides on switched communication.
[28-Apr-2014] Some notes from Radu's lecture on ADSL FDM and statistical TDM. The statistical TDM example in particular may be helpful for the chapter 8 homework problems.
[25-Apr-2014] The 10th edition of the Stallings textbook seems to be missing any real discussion of statistical multiplexing. Here are some pages from an earlier edition of Stallings on statistical multiplexing.
[25-Apr-2014] Some slides on error control.
[22-Apr-2014] A nice TCP sliding window animation (Flash) showing how TCP can dynamically adjust the length of the sliding window.
[22-Apr-2014] Some slides on flow control.
[17-Apr-2014] Some slides on forward error correction.
[17-Apr-2014] Flash-based Hamming (7,4) code demonstration.
[15-Apr-2014] Some slides on error detection.
[10-Apr-2014] An interesting article on understanding TCP sequence and acknowledgement numbers.
[08-Apr-2014] Lecture slides for digital signaling and analog signaling from Stallings 5.1-5.2.
[04-Apr-2014] A table comparing the spectral efficiency of several modern wireless systems.
[01-Apr-2014] Matlab attenuation calculator. Edit this script with your link parameters and run it in Matlab to see the attenuation of the link under both wireless path loss models discussed in class. The script also plots the attenuation of a cable with a specified dB attenuation per 100 meters for comparison.
[01-Apr-2014] A link to the Parsons Mobile Radio Propagation textbook which has a detailed derivation of the line-of-sight channel model with a single reflection (see, in particular, page 25).
[28-Mar-2014] An example of a Yagi TV antenna with 15.7dBi gain. Be sure to click on the specifications and technical data (under the documents tab).
[28-Mar-2014] You can get a report on the signal strength, type of propagation, distance, and azimuth of the various terrestrial TV stations near a given address at tvfool.com. Click on the link to "Check your address for free TV".
[28-Mar-2014] US frequency allocation chart (pdf).
[28-Mar-2014] Some technical details on how you can use DNS and a virtual private server to overcome IP-based geographical content restrictions.
[28-Mar-2014] Another interesting article about DNS and how it can be used for political purposes.
[26-Mar-2014] Some clarification on dB, dBm, and dBW.
[25-Mar-2014] Homework and lab assignment 2 posted.
[25-Mar-2014] Slides regarding some basics of the domain name system.
[18-Mar-2014] Comms/networking story of the day: Google DNS server briefly hijacked. More details on these types of attacks can be found here.
[17-Mar-2014] An email was sent to the class mailing alias ece2305@ece.wpi.edu today. If you did not receive this email, please contact Prof. Brown.

general

The required course textbook is Data and Computer Communications, 10th edition, by William Stallings.

The course syllabus (pdf format) including expected course outcomes, grading information, and late policies.

ECE2305 academic honesty policies.

ECE2305 students with disabilities statement.

homework and lab assignments

homework and lab assignment 1

Homework and lab assignment 1. Due promptly at the start of class 25-Mar.

Solution.

homework and lab assignment 2

Homework and lab assignment 2. Due promptly at the start of class 01-Apr.

For question 3 and questions 18-20, the DNS servers you select may refuse your DNS query (I had trouble getting this to work). If you are having problems with question 2, you can query the DNS server for another university in Asia (rather than a Yahoo mail server) but still specify the server from question 2. For questions 18-20, it seems that bitsy.mit.edu will refuse the request. You can use 8.8.8.8 (the Google Public DNS) or 208.67.222.222 (OpenDNS Public DNS) for these questions.

For parts II and III (ipconfig and Wireshark), I recommend you do this part on a Windows or Linux computer. Determining the DNS configuration and flushing the DNS cache is tricky in OS X. OS X has its own way of doing address resolution and will probably be easier to just do these parts of the assignment on a Windows PC.

Homework solution.

Lab solution.

homework and lab assignment 3

Homework and lab assignment 3. Due promptly at the start of class 08-Apr.

For question 5 in the lab assignment, the response I got from the server did not have a http.last_modified field. You can, however, filter by http.last_modified in the Wireshark filter and probably find another HTTP response that has this field. Please be sure to discuss what you did in your lab report.

For questions 8-11 of the lab assignment, I was unable to observe the "conditional get" when loading lab3part2.html. I'm not sure why this is (it might be because the html file is very small). If you are having the same problem, you can try http://spinlab.wpi.edu/wireshark/alice.txt. You should see at least one "HTTP/1.1 304 Not Modified" response in this case. The point of this part of the assignment is to see that the web server doesn't send the whole file again if you request it shortly after you first requested it. The web server sends a much shorter "not modified" message that allows the browser to use the local cache instead.

Homework solution.

Lab solution.