Network Investigation/Blackbox lab

This lab uses the Genie lab environment. Note, that this is a different ISO than the one used in the other labs. The other ISO does not contain the Blackbox lab, so if you do the lab at home you need to download new blackbox ISO.

To start the lab, boot your computer from the CD. When the computer has started click the "Start Blackbox lab" icon once.
You will be presented with three terminal windows, these are windows into Catfish, Starfish and Blowfish which are
the virtual computers you will use for this lab.

The Assignment

Your goal is to investigate the network connectivity between three computers; Catfish, Blowfish and Starfish
The main tools needed to explore the network are:

Iperf

A tool to measure network performance
Iperf daemons are running on Catfish, Blowfish and Starfish.
A simple bandwith test from Starfish to Blowfish is shown below.

 
   starfish:~# iperf -c blowfish
   ------------------------------------------------------------
   Client connecting to blowfish, TCP port 5001
   TCP window size: 16.0 KByte (default)
   ------------------------------------------------------------
   [  5] local 192.168.0.2 port 3690 connected with 192.168.1.2 port 5001
   [  5]  0.0-101.3 sec  24.0 KBytes  1.94 Kbits/sec
   starfish:~#

Ping

Sends ICMP ECHO_REQUEST packets to network hosts.
Ping can be used to measure packetloss and latency between two endpoints.

   blowfish:~# ping -c 9 catfish
   PING catfish (192.168.2.2): 56 data bytes
   64 bytes from 192.168.2.2: icmp_seq=0 ttl=61 time=1618.5 ms
   64 bytes from 192.168.2.2: icmp_seq=1 ttl=61 time=860.2 ms
   64 bytes from 192.168.2.2: icmp_seq=2 ttl=61 time=844.7 ms
   64 bytes from 192.168.2.2: icmp_seq=4 ttl=61 time=844.4 ms
   64 bytes from 192.168.2.2: icmp_seq=3 ttl=61 time=2852.7 ms
   64 bytes from 192.168.2.2: icmp_seq=5 ttl=61 time=860.7 ms
   64 bytes from 192.168.2.2: icmp_seq=6 ttl=61 time=861.1 ms
   64 bytes from 192.168.2.2: icmp_seq=7 ttl=61 time=844.8 ms
   64 bytes from 192.168.2.2: icmp_seq=8 ttl=61 time=2851.6 ms

   --- catfish ping statistics ---
   9 packets transmitted, 9 packets received, 0% packet loss
   round-trip min/avg/max = 844.4/1382.0/2852.7 ms

Traceroute

Prints the route packets take to a network host.
Traceroute can be used to give some insight into which hosts a packet is routed through.

   catfish:~# traceroute starfish
   traceroute to starfish (192.168.0.2), 30 hops max, 38 byte packets
    1  kulangath-0 (192.168.2.1)  1.242 ms  0.798 ms  0.748 ms
    2  diablo-3 (10.0.0.13)  608.071 ms  618.242 ms  623.571 ms
    3  starfish (192.168.0.2)  634.655 ms  619.056 ms  2647.875 ms

Tips and tricks

We encourage you to read the manual pages for the tools you use, they provide good information that will help you interpret the results. Man-pages can be a bit intimidating at first but it is well worth it to get used to them. Alternatively you can search the web for information about how the tools work but information acquired in this way is less reliable.
Run your tests several times. The lab environment is emulating the entire network, and unless you have a very powerful computer you might experience extreme results for some testruns. This is something you must account for when doing your analysis.
Motivate your conclusions well. A rough estimation with good motivation is far better than an exact value with a poor motivation.

The report

The report should have a cover page with the name of the lab and the students who have taken part in the solution.
We expect you to present a schematic of how the unknown network cloud is structured, detailing the possible limitations of each link and intermediate network host.
Along with this schematic, you should provide descriptions on how this information was obtained, with discussions about possible margins of error, alternative interpretations etc. Logfiles are good complements, but should be accompanied by a discussion on what conclusions you draw from them.
The length of the report, images and logs not included should be no longer than 5 pages.

Hand in

The report should be handed in to the lab assistants pigeon-hole no later than 16:00 on the 19:th of december.
Questions regarding this lab can be directed to Thabo.