Compsci 82, Fall 2009, DNS and Open Source Questions 9/7/09

By entering your name/net-id below you indicate you are in class on September 7 to answer these questions and that you have answered them. 


Name: ___________________    Net id: _______ ||| Name: ___________________    Net id: _______

						 					    						 					    
Name: ___________________    Net id: _______ ||| Name: ___________________    Net id: _______
In a 2008 case, a federal US District judge ordered wikileaks.org to be "shutdown" by having its domain name registrar disable the domain name. Wikileaks is a whistleblowing site that claims "We are of assistance to peoples of all countries who wish to reveal unethical behavior in their governments and institutions. We aim for maximum political impact.

In a Feb 20, 2008 NY Times article reporting on the disabling of the domain name this report is given:

The order had the effect of locking the front door to the Wikileaks.org site --- a largely ineffectual action that kept back doors to the site, and several copies of it, available to sophisticated Web users who knew where to look.

  1. Explain in a few words why people were still able to access Wikileaks at http://88.80.13.160/ despite the removal of www.wikileaks.org from the domain name system.
  2. Explain in a few words why the mirror site http://wikileaks.de was still available even though wikileaks.org was not.

  3. Using the network solutions web-based WhoIs service indicates that the IP address 211.151.227.142 corresponds to the Asia Pacific Network Information Centre with a CIDR of 210.0.0.0/7 and a range of addresses from 210.0.0.0 -- 211.255.255.255. How many addresses is this expressed as a power of 2? Explain how you arrived at your answer.

  4. If IANA were to allocate every possible IPv4 address at the rate of one billion addresses per second, how long would it take to run out of addresses? Justify your answer. (approximate is ok)
  5. If IANA were to allocate every possible IPv6 address at the rate of one billion addresses per second, how long would it take to run out of addresses. Justify your answer. (approximate is ok)
  6. BGP routers may exchange routing tables --- a full table contains about 300,000 entries. Why is this number so much smaller than the number of IP addresses in use in the world which is over four billion?

  7. Which do you find more surprising, that Apache webservers (open source) account for 50% of total market share among webservers or that Microsoft (proprietary) accounts for roughly 25% of the market? Why?
  8. Eric Raymond wrote "given enough eyeballs, all bugs are shallow" in reference to Open Source software development. In a sentence or two, what does this mean?