Online Computing Day 2008

The Computing Day Materials

Computing Day 2008, originally scheduled for Oct 14, was converted to an online event. Students from area schools read through the following materials and answered the set of questions shown below. The winner of this contest was chosen from among those who best answered the questions. A student from Greensburg Salem High School won the 2 GB flash drive prize.

The Contest Questions and Answers

The following are the questions used in this contest, along with the answers to those questions.

Question 1

The ACM site quoted CNN Money Magazine that, as of 2006, the best job in America was:

a) network administrator
b) web developer
c) software engineer
d) physical therapist
e) none of the above

Answer: c
All of the above fields were highly rated, but software engineer was at the top.

Question 2

According to MySecureCyberspace, cyber criminals can get you to help them by:

a) supplying your username and password when asked to do so in an email
b) supplying your credit card number when asked to do so in an email
c) installing malware on your computer that let's them use your computer remotely
d) all of the above
e) none of the above

Answer: d
MySecureCyberspace gives several examples showing that giving out personal information can allow cyber criminals to perform actions in your name, which is very dangerous. They also talk about how cyber criminals try to install malware on your computer (by all kinds of means, including fooling you into installing it). That malware can then allow the criminals to use your computer remotely to send spam, to attack other computers, etc., perhaps without you being aware of it.

Question 3

The student in the MySecureCyberspace article who was bullied while sitting in her own bedrooom was bullied by means of:

a) emails
b) instant messaging
c) phone calls
d) instant messaging and phone calls
e) emails and instant messsaging

Answer: e
Although any of the above could be used, the article stated that this particular students was bullied through emails and instant messaging.

Question 4

According to the ComputerWorld article, which state is in a legal battle with a voting machine vendor over votes that were not counted in a recent election?

a) New York
b) Ohio
c) Pennsylvania
d) Florida
e) none of the above

Answer: b
This appears at the end of the ComputerWorld article, with links to further information.

Question 5

For this same voting machine problem in this same state, what does ComputerWorld say was the cause of the dropped votes?

a) errors in the software
b) hardware problems
c) the antivirus interferred with the voting software
d) hackers broke into the voting machines
e) none of the above

Answer: a
Although the vendor originally claimed that the antivirus software interferred with the ability of their machines to correctly count all the votes, they now have admitted that programmer errors caused the problem. The software was thus faulty.

Question 6

According to ComputerWorld, Pennsylvania uses which of the following types of voting systems?

a) hand-counted paper ballots
b) optical scan
c) DRE
d) a and b
e) b and c

Answer: e
Pennsylvania uses optical scan machines to scan printed ballots, DRE (direct recording electronic machines), and other methods, though not hand-counted paper ballots.

Question 7

This question will test your ability to understand technical information about networking and computer security. Computers on a network send data from one computer to another in small packets of data. One type of packet sent from one computer to another is called a ping. The receiving computer should send back a ping reply packet. This is used to tell the first computer that the second computer received the ping without any problem. Each ping and ping reply packet contains the address of the computer sending the packet and the address of the destination computer. So, if the computer at address 10.30.20.4 should send a ping to the computer at destination address 10.30.20.19, the second computer should send a ping reply back to the computer at address 10.30.20.4. The situation can be complicated by other factors. For example, it is possible to send packets of data to all of the computers on a network by using a so-called broadcast address for the destination. Also, a hacker can use a fake source address, in essence indicating that the packets sent by the hacker come not from him, but from the computer at that fake source address. Now for the question: What would happen with the ping replies if the computer at address 199.130.77.12 were to send 100 ping packets to the broadcast address of Saint Vincent College, but with a faked source address of 111.104.56.3? Assume that nothing blocks any of the packets and that Saint Vincent College has 200 computers running on its network.

a) 100 ping replies are sent to all of the computers at Saint Vincent College.
b) 100 ping replies are sent to the computer at address 199.130.77.12.
c) 100 ping replies are sent to the computer at address 111.104.56.3.
d) 20,000 ping replies are sent to the computer at address 111.104.56.3.
e) 20,000 ping replies are sent to the computer at address 199.130.77.12.

Answer: d
This question requires some thought. Each of the 100 ping packets gets sent to all 200 of the Saint Vincent College computers. Each of those computers sends a ping reply. That's 100 times 200 = 20,000 replies. Where do those replies go? They go to the source address in the pings. That's the only way the Saint Vincent Computers have of knowing where to send the ping replies. Of course, that source address was a phony address of 111.104.56.3, and not the address of the real sender. The computer at address 111.104.56.3 gets the 20,000 ping replies. This is a method that hackers use to attack a computer with a large volume of packets. The computer at 111.104.56.3 might be overwhelmed with all of this network traffic. It might cause that computer to crash or to be unable to perform normal network functions while the attack is underway. This particular type of attack is called a smurf attack and the Saint Vincent College network was used as a "smurf amplifier" to multiply the number of packets sent to the victim computer. Note that if the victim investigates, the Saint Vincent College network appears to be the source of the attack, not the hacker. Happily, firewalls can prevent a lot of this nonsense from happening.

Conclusion

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Maintained by: Br. David Carlson
Last updated: October 29, 2008