Cryptography

The History and Mathematics of Codes and Code Breaking

Tag: little brother (Page 1 of 4)

Little Brother Links

A few Little Brother links for you, most of them mentioned in class...

  • Cory Doctorow blogged about my blog post about our in-class debate map activity.
  • On Twitter, I asked Cory Doctor about the terms "surveillance" and "security" as they apply to this debate. Here's what he said.
  • Here's that streamgraph showing the use of words in Little Brother from start to finish.
  • Cory Doctorow wrote a sequel to Little Brother called Homeland that describes the continuing adventures of Marcus Yallow.

Little Brother Debate Map (2015)

I snapped a photo of the debate map we constructed during class on Monday. We'll talk more about Little Brother in class tomorrow, and I thought you'd want a copy of the debate map for reference. Recall that orange Post-it notes captured pro-security arguments made by characters in the novel, while magenta Post-it notes captured pro-privacy arguments. Click on the image for a better look. And if you're really interested, check out the 2012 debate map and the 2014 debate map.

Little Brother Debate Map 2015

When privacy becomes a privilege

Since Marcus was questioned by the National Homeland Security after “being at the wrong place at the wrong time”, his freedom has been taken away from him. During the journey, he has fought himself all the way to the end of the story for his rights,  freedom and privacy. In this specific setting, these rights, freedom and privacy are no longer what we “suppose to have”, but rather a privilege that need to be earned.

Coming from a country where websites or tools such as Google, Facebook, Gmail, and Twitter are all blocked, I witnessed people’s different attitudes and approaches to this seemingly harsh censorship. Some would, as Doctorow suggests, getting around the Great Firewall of China by using an encrypted connection to computer in some other country (p. 112); some would physically get through this firewall, which is what I ended up doing. Either way, people would take some risks or make some sacrifice for the privilege to own their privacy. On the other hand, others, probably happen to be the majority of the population, either don’t really care about this censorship or choose to do nothing with it.

That really got me thinking, why would we care about privacy anymore while a lot of people around us seem to think it’s no big deal? And again I asked the question I asked when I wrote the first paper: why would we care about data mining if we are doing nothing wrong? Doctorow offers his answer to the questions in “Little Brother”– because privacy does matter. It is not about doing something wrong or shameful, but about doing something private, about having some corner of our lives that is ours, and knowing no one else gets to see it. (p. 57)

The False Feeling of Security

I greatly enjoyed the class debate passages (p. 92-93, 175-182) in Little Brother. In the first debate, Marcus brings up the effects of terrorism and the problems with reactions to it.

Marcus' argument about the effects of terrorism involves the types of reactions societies have to acts of terrorism. Post-attack, his school system decides to install cameras in every classroom and hallway. He argues that this reaction gives into the terrorists' goals, because it fosters fear in the students and does nothing to truly protect them. In general, I agree with Marcus. The cameras give a false sense of security, pretending to be preventative measures when in truth they can do nothing to defend the students in the event of an attack, or to prevent one from happening. All the cameras do is watch and wait, ready to catch evidence to incriminate terrorists, which will be of no comfort to the victims of the attack. Therefore, the cameras are not much more than constant reminders of the events of the past and of all the fear there is to be felt in this world.

This concept reminds me of the heightened security after terrorist attacks, like 9/11. Post-9/11, airport security was entirely remade, and incredibly tight procedures were created. However, while some of these procedures can prevent and protect, they have their issues. The new procedures in any post-attack scenario increase security on the target of the attack--in this case, planes. The problem is, airports and planes are just one potential target, and it's unlikely that, having used that method, a terrorist group will choose to use it again. This isn't to say that increased security and tightened protocols are poor uses of resources. They are, of course, necessary and good. However, they do not automatically mean that everyone is safe. In fact, it seems to me that even as new security measures are important, they also allow the terrorists to accomplish their goal. Without the precautions, we leave ourselves open to other attacks via the same battle-tested methods. However, with the precautions, we focus our attention on one group of targets, associate fear with said targets for some period of time, and use valuable (but necessary) resources to defend them, without any real knowledge of the next potential target. These are the problems of being on the defensive, but they are issues to which I believe cryptography can hold the answers.

Why Do We Want Privacy?

"It's not about doing something shameful. It's about doing something private. It's about your life belonging to you" (Doctorow 57).

The idea in Little Brother that made me think the most was the idea of personal privacy and why that is so important. On page 57, Marcus compares a betrayal of personal privacy to a situation where you had to use the bathroom in a glass box in the middle of New York City every time you had to go. Everyone uses the bathroom, but it is a private and personal part of our lives, not something we want to share with everyone. So while Marcus didn't have anything really illegal, and definitely not at all related to the terrorist attack, on his phone, he didn't want to give "severe haircut lady" his password because his phone had private information that was his personal space. Throughout the novel, Doctorow explores the balance of protecting privacy and stopping terrorism. Homeland Security's efforts to find terrorists causes divorces and fights, things brought to light when their privacy was compromised. Xnet begins in the first place so kids can play video games and email away from the snooping DHS. This widespread desire for a private corner of our lives is why cryptography is so prevalent in our lives. As Vanderbilt students, our emails, web browsing, and phone calls are likely (and hopefully) nothing illegal: emailing professors about homework, calling home to parents, and ordering a pizza. But that doesn't mean that we want everyone to be able to see that. Cryptography allows everyone a sense of privacy and a way to create that privacy. However in this novel, Doctorow asks an important question: how much of this personal privacy are we willing to give up in the face of terrorism? Whether you agree more with Marcus or his dad, I think everyone would agree that the government in Little Brother gave far too little respect to personal privacy.

Inaccurate Accuracy

Though there were a lot of interesting insights made throughout the novel regarding cryptographic security, the point that most stood out to me had to do with the "paradox of the false positive."  In chapter eight of the novel, Marcus comes up with the idea to clone arphids in order to create a high number of unusual travel patterns and consequently bog down the DHS's tracking systems. He goes on to describe how anytime you are trying to collect data on a wide scale, lets say for example from one million people, the test's percentage of accuracy needs to be the same as the uncommonness of the thing being looked for. For example with one million people being tested, a 99% accurate test would still find 1,000 positives, which would be very unhelpful if you're looking for only one specific person. The more people, and the less common the variable you're searching for, the more unusable your test becomes.

What I thought was so interesting about this point is that when looking at the math for this sort of data mining, it seems so illogical. The probability of finding usable data in this manner becomes more and more difficult as the amount of data increases. However, just hearing the phrase "99% accuracy" creates an inherent false sense of security. This false sense of security becomes dangerous when we rely heavily on technologies such as these to find information for us. What happens when the accuracy is lower than 90%? Lower than 80%?

One thing we have discussed in class more than once is the idea of data mining, especially in schools, to attempt to find patterns that would predict crime before it occurred. The point that always gets brought up in favor of this sort of data mining is that it potentially could keep students safe, which of course would be beneficial. However, lets say that these measures were implemented at Vanderbilt, with 12,725 students, and the test had a reasonable 95% accuracy rate of finding potential threats. Theoretically 636 students could be found potential threats by the system. It's improbable and illogical to question over 600 kids in order to find a possible one or two actual suspects. Though neither Marcus nor I were making the claim that all data mining is useless, seeing the numbers on how useful it really is puts the idea into a better perspective.

Cryptography by the People for the People

The passage that stuck out to me the most from the novel was Marcus’ description of the use and benefits of cryptography from page 57. Even though it’s at the beginning of the book, this passage gets to the core of how cryptography works for us today. Cryptography is used by everyone because is as accessible to everyone. Thankfully, our government does not have a monopoly on cryptography; “the math behind crypto is good and solid, and you and me get access to the same crypto that banks and the National Security Agency use” (Westerfeld 57). Because it is so widely used, we can be sure of its effectiveness.
The quote continues to discuss how cryptography is useful to us today. Even if we do not have anything to hide, “there’s something really liberating about having some corner of your life that’s yours, that no one gets to see except you.” This reminds me of the article I read regarding the actions of the National Security Agency and invasion of civilian privacy due to bulk data collection. The fact that personal information as well as government intelligence is encrypted using the same means shows that the government has access to all of our information as well. This is not a bad thing; access to this information can be useful in ensuring peace. The question still remains: when does government access of individual data cross the line from protection to trespassing?

Progression is Activism

Although at first I was a little miffed about the idea of reading an entire novel over break, but it was actually a pretty relaxing read and some points the author made were really thought provoking. Sometimes I felt he was trying to be too hip - I suppose this is a common occurrence in a lot of teen fiction - every time I read "total horn-dog" I was thinking, "what?" But that's neither here nor there. There were a number of quotes that I really thought about, like when Marcus was arguing for the absolute protection of the Bill of Rights, and the total non-professionalism some of the authority figures in the book seemed to exude, but Marcus also pointed out something very important. "I can't go underground for a year, ten years, my whole life, waiting for freedom to be handed to me. Freedom is something you have to take for yourself." Inspiring, isn't it?

Truly, nothing will be accomplished by passivity. The constant activism and solving problems is what propels movements forward - awareness will get something started, but there must be steps taken beyond that. Cryptography is similarly a constantly evolving subject, requiring analysis that is always considering different options and perspectives. It couldn't progress so efficiently if cryptanalysts were always waiting for other cryptanalysts to decipher notes themselves - and in many cases, that's exactly what they don't want to happen.

The False Positive Paradox

While I had previously worked with false positives in various statistic problems, I never considered the implications behind it. Cory Doctorow addresses this "false positive paradox" in his book Little Brother.

In the story, the narrator, Marcus, talks about a "99 percent accurate" test for "Super-AIDS" (Doctorow 47). However, this means the test is one percent inaccurate. One percent of one million is 10,000. Only one of those people will actually have the disease, and thus, the "99 percent accurate test will perform with 99.99 percent inaccuracy" (Doctorow 47).

This was extremely interesting, as I had never considered how inaccurate these tests really were. The statistics and numbers had always seemed solid. It made sense, and 99% seemed like an extremely high percentages. But Doctorow makes an intriguing analogy. Pointing at a single pixel on your screen with a sharp pencil works. However, pointing at a single atom with a sharp pencil would be extremely inaccurate. This essentially highlights the flaws in any test that could potentially produce false positives. Whether detecting diseases or terrorism, these tests could result in large wastes of resources, such as time and money.

This could also be connected to the process of cracking ciphers. For example, when searching for cribs in an Enigma deciphered message, a crib may make sense in a particular context but could turn out to be an incorrect decipherment for the whole message . Even in general cryptanalysis, you could potentially make progress on deciphering a message. After hours of working on a message, you could realize that you made a mistake originally and your previous progress had simply been a "false positive". Clearly, false positives can be quite dangerous and misleading. The false positive paradox further magnifies the huge effect these false positive readings can have on carrying out important tests or examinations, and the consequences could be devastating. Imagine administering a drug thought to combat a certain disease to a patient who really didn't have the disease. Because the patient was perfectly fine, this drug actually resulted in the patients' children having birth defects. A simple false positive could cause tragic repercussions.

I Don't Care.

The best security measures in the world, even the seemingly flawless and fool-proof of systems, can be beaten by the simplest of things: the failing to enforce it.

In Little Brother by Cory Doctorow, there was a point in which Marcus received an email from some followers who were caught jamming by some cops. However, after waiting to be interrogated in one a prison truck, they were released after a new shift of cops decided that they had "better things to do than bother [them] with more questions."

Isn't this so telling of our relationship with technology? It is the whole "Technology is only as good as the person using it" argument all over again. If someone somewhere along the chain of command decides that he/she doesn't care, the whole system goes down the drains.

This is also evident in other historical cryptographic events as well. The Enigma machine was cracked partially due to the fact that cryptographers got lazy. They had predictable language and sometimes even predictable keys (e.g. initials of loved ones). Without these, the Enigma could have been "uncrackable" for a much longer time.

This story from the book also interests me because it discusses human motivation in an almost real-world setting. Antoine de Saint-Exupery once said, "If you want to build a ship, don't drum up people to collect wood and don't assign them tasks and work, but rather teach them to long for the endless immensity of the sea." The DHS did not properly motivate their employees to ensure that they would follow through with their commands which led to failure in this situation. People will only go so far for so long when listening to orders before they give up. This can be due to any number of reasons. In one scene, when Marcus invited Ange over to use the XBox and chill for the evening, Ange points out one of these reasons and notes that Marcus's "only weapon is [his] ability to make [the DHS] look like morons." She points out that in order to derail the DHS, Marcus needs to undermine the motivation of the DHS to continue what they were doing.

 

Page 1 of 4

Powered by WordPress & Theme by Anders Norén