Description
CS 39006: Networks Lab
I guess all of you the story behind the Internet.org and FreeBasics services
(https://en.wikipedia.org/wiki/Internet.org) that was developed and popularized by
Facebook and have seen a lot of debates later on before being banned in many
countries in India. In this assignment, we’ll analyze a traffic trace collected while using
the Freebasics service to explore a few of the interesting stuff regarding the range and
scope of the Freebasics service.
One of the important aspects of the FreeBasics service is that how many users from
which countries have accessed the service. For this purpose, we had developed a web
service called LearnBasics (a simple website for teaching basic English words to
students), deployed it on a cloud server, and registered the service with FreeBasics.
The domain name for this service was http://learnbasics.mpi-sws.org (the domain is not
active right now). The users having the FreeBasics app installed on their mobile can
access this LearnBasics service through Facebook’s FreeBasics app.
FreeBasics works in the following way (see the following diagram). Facebook used to
run a FreeBasics HTTP proxy (Internet.org) in different parts of the globe. When a user
wants to access a FreeBasics service (like LearnBasics), the request goes through the
FreeBasics Proxy and the ISP makes that service free for the user.
We have collected a pcap trace at the LearnBasics server. The pcap trace is available
here —
https://drive.google.com/drive/folders/1VFTwFDkFAsACXJfyBGCUtr7-XexWiGnG?usp=
sharing
Your task will be to write a python script to find out the answer to the following
questions.
(a) What are the different countries from which the LearnBasics service has been
accessed via FreeBasics?
(b) How many users from each of those countries have accessed the service via
FreeBasics?
Execute the following steps to do this.
1. Use the tshark tool to extract only the HTTP Requests from the the pcap file
and generate a new pacp with the filtered HTTP Request packets.
2. Use the tshark tool to covert the new pcap (with only HTTP Request packets) to
a xml file.
3. Write a python script that will take this xml file as the input and will produce a csv
file in the output. The csv file will have the following two fields —
a. Country name
b. Number of users who accessed the service from this country
Sample Input and Output:
Say, the xml file name is http.xml, and the python script is parse.py.
>> python parse.py http.xml
The output is written in data.csv
The file data.csv will contain something as follows.
KENYA 112
COLUMBIA 32
SENEGAL 34
EGYPT 99
IRAQ 56
Important Points:
1. Note that the request has been forwarded by a HTTP proxy, and the trace has
been collected at the server. So, the Source IP field at the IP header may not
contain the IP of the user. You should check the trace and find out which field
contains the IP of the user.
2. Some users might directly access the service via the web, and not via the
FreeBasics app (not through Internet.org proxy). We are only interested in the
users who accessed the service via the Internet.org proxy. You should check
this.
3. You can use the python-geoip package to find out the geolocation for an IP,
which returns the country code.
4. You can use the pycountry package to find out the country name for a country
code.
Submission Instruction:
You need to submit the python source via Moodle by the deadline. Your Python source
should have sufficient comments explaining the steps you have used in the code.
