Cryptography

The History and Mathematics of Codes and Code Breaking

Author: Elton Page 1 of 2

Judging criteria for the debate

As a jury of a debate, I would like to consider several issues as the judging criteria for the debate on Monday.

First of all, the basic points for pro team and con team must be explicit and reasonable. In their first round, they must build at least one solid point of view, which should be prepared well before the debate. What I expect to hear about is the real voice for the citizens that which one is more important, privacy or security, and why. The best form of their speaking is the combination of points and examples in order to make the point more convincing.

Secondly, after hearing the point of the opposite team, they should know what is the core statement of the opponent and build up an effective counterpoint for that. For example, if the pro team states that electronic surveillance could help track criminals, I expect the con team to consider that sometimes it does not work with the system and there might be false positives that lead to the wrong direction and harm innocent people.

Thirdly, they should also learn about the possible weakness of their own points. If they could point out the weakness by themselves and do concession. Then they actually effectively eliminate one possible point of opponents. Both teams should prepare these ideas well before the debate so that they could react quickly in the class.

People cannot convince others thoroughly, but they could use their ideas to influence others' thoughts, at least make others agree to part of their points and consider the issue from some new aspects. If they made it in this level, then they might do better than the opposite side and win the debate.

Advices for college students

After stepping into college, the internet becomes more and more popular in our daily life. Nowadays we purchase things through the internet, we upload our assignments through the internet, we book our session through the internet. Meanwhile, internet privacy gradually becomes a problem.

The first advice I would give a college student is that do not use the same password for many websites. Especially in the modern society, all of your accounts are connected. Some websites have strong security systems but some don't. If one of these websites was invaded and your password was decrypted by the hackers, all of your information on other websites is bare as well. For example, we may correlate our Facebook account to a video game account. If the security system of the game company was weak and the hacker got the information of your account, your Facebook is going to be invaded easily.

The second advice would be that try to avoid logging in your account on public devices. You never know what will happen to others' devices. Even though sometimes we can choose to not save the password. There would be cookies that can track your account and. Especially when it comes to your payment method, such as the credit card information. There might be unknown computer viruses that were implanted in the public computer system, which means your information could be stolen by others without any trace.

Finally, I would recommend the Apple productions for their security system. All of their devices are connected if you log into your account. If someone else wants to log in your account on a new device then they must get your approvement because there will be a required verification code showed on your old devices. Also, the "Find my Apple" function is useful for finding lost. Even though your mobile phone was turned off, you can trace its location in 24 hours, in order to find it in time.

A Good Podcast By Using Excellent Introductions and Voices

After listening to the podcast “Something Out of Nothing” by Maria Sellers, I found many interest points about this podcast, both the content and the structure. Also, I learned several useful ideas about the production of a podcast.

First of all, The title of the show notes of the podcast,  “Something Out of Nothing”, would definitely draw everyone’s attention in a series of titles and push the audience to click into the podcast. After that, the show notes provide a great introduction to the whole story. We could know that the story is about the true identity of Shakespeare and the hide secrets in his plays. However, in order to learn more about the interesting story, we have to move on.

I have to admit that the introductory music is excellent. It successfully builds a mysterious atmosphere of the whole story and it is also used between every section of the whole story. Each time this little period of music shows up, I am looking forward to learning about a new interesting part of the story of Shakespeare.

Another voice she combines in her podcast is the monologue of Shakespeare. This part after the intro music also helps to build the atmosphere and leads to the topic. She also read several pieces of Shakespeare’s work to enrich the elements of the whole podcast.

To summarize, the podcast “Something Out of Nothing” helps me a lot on the producing of my own podcast. I learn about the use of music between each part and introduce various elements in the story. Also, an attractive title and proper show notes could attract more audience to listen to my podcast. I really appreciate the reasonable structure and exquisite production of this podcast.

Social Media provides more gaps between parents and teens

"Social media has introduced a new dimension to the well-worn fights over private space and personal expression."

Have you ever hide part of your school life as secrets from your parents through social media? Shared with your friends that you played a trick with your teacher in high school but hide it from your parents? Well, after the birth of social media, teens gradually share less with their parents. Even stay at home, we would not talk about our real life with our parents but chat with our friends through the Internet.

This phenomenon is related to the purpose of social media. As it showed up in our lives, social media become a perfect tool to improve the relationship between friends. People can not only chat in real life face to face but also chat online at any point. Meanwhile, social media also aggravate the tense relationship between parents and teens. Before the era of social media, parents worry about what teens had done outside and tried to talk with them when they back home. Teens enjoyed their time outside and had to face their parents' question and chatter. However, through the social media, teens could bring their social life and resistance to parents back home. They could lock themselves in their bedrooms and still chat or post with their phones and laptops. It's much harder for parents to try to learn about their children's social lives.

Definitely, teens are happy with this change. They have more rooms and freedom now. They could hide their secrets from their parents by simply finishing a privacy setting. At the same time, the gaps between teens and parents become larger and larger. Parents could no longer know what teens want to hide and start to worry more. With almost a blank impression about what their children have posted on Facebook or Instagram, as well as what their children have said to their friends, parents will imagine possible bad manners that kids may be accustomed to. Those imaginations then become new gaps that teens won't talk to their parents about but parents keeping worrying.

 

Be responsible for creating possibility of crime

If a public software is utilized by the criminal organization or foreign government, its maker definitely has partial responsibility for that. If the software make the criminal behavior possible, then it becomes part of the criminal behavior. When the software makers publish their work on the internet, they should consider its safety and take action to protect the privacy and security of its possible user. For example, if there is a effective encryption for the password of its users, the possibility of information stealing is smaller in this software. Also, the software maker should keep an eye on his or her software in order to check its operation and safety. If there is something wrong happening, they should notice it and take action in time, so that there won't be worse outcome.

Meanwhile, the user should be responsible for their privacy and security on the internet as well. If you choose a weak password and never change it, you can't blame it on others but yourself. Stealing information is taking the advance of both weak system of the software and the weak protective actions taken by the user. We can't stop all the criminal behaviors through the internet, but we could at least pay attention and put our effort into the protection of our own privacy. Therefore, both the software maker and user are responsible for what they have done on the internet, and both them should be more careful about protection of the private information.

Breaking Codes Is Much More Difficult In Practice

In Chapter 3, Singh provides an example of breaking codes with keywords and makes everything seems quite easy. However, in practice, breaking such a code is definitely difficult and needs a lot of time and work.

Say you have a message which is enciphered by using a keyword as long as the plaintext. The first thing is that you can't use the Kasiski examination technique. The only way to start is to try some common words to find a clue about the keywords. In Singh's example, he assumes that the first word is "the". That is a reasonable strategy because "the" is one of the most frequent words in English. However, what if the first word is not "the" but one of the other common words? There is a problem that if the common word in the plaintext is a word with only one or two letters like "a" and "in", Singh's method described in the book will be useless that he couldn't find any corresponding key letters because there are too many possible combinations of two letters to check one by one. Also, Singh's deduction of the construction of the keyword is actually a special situation. Consider if you guess "CAN" and "YPT" in the keyword, it's actually hard to correspond them to "Canada" and "Egypt" and it must take a long time to try all the possible combinations. Finally, the work to find out the last four letters in the keyword is also a hard work which needs a lot of time even with the clue that it is a country name, let alone that in a usual time we don't have an explicit clue like the country name. Singh just assumes he is the most fortunate one that his every shot is perfect when breaking this code.

Besides all of these above, there is another thing we should know that probably we would face the problem of false positives in our breaking procedure. There are thousands of combinations with several certain letters and short words, how could we make sure that we get the right one? Each time we go on with an assumption means that we will spend a lot of time on this assumption and if we failed, everything needs to run again to check the next one.

What Would I Give Up To Feel Safer

To be honest, I am not good with the USA Patriot Act, because it means I have no right to hide any secrets. If somebody could look over all my private staffs without my approvement or even without my acknowledgment, I will feel invaded. However, I have to admit that there is terrorism in this world and our safety needs to be protected. The USA Patriot Act is useful to protect the country. The "watchdog" role played by news media and improved power of FBI did protect us after the 9/11 attacks. Therefore, I would like to sacrifice part of my privacy, but not all of it.

What I agree to give up, is the information on everything I've done and anything I've told to others, like the purchasing record, messages on social media, and all of my identity. In my opinion, these pieces of information are enough for the government to assess my possibility to do some violent behaviors as well as every individual. For example, if someone is going to make a terrorist attack, he has to purchase items like guns or bombs, reach out to terrorist organizations, and leave messages to his partners. One cannot finish a terrorist attack without any clues before in front of the public. To investigate related information is enough to prevent a possible violent behavior.

What I disagree to give up, is what I regard as real privacy. I used to write my diary in the memories of my cell phone. I have never shown it to others because I usually hide my secrets in it. How could it harm others if I let nobody see it? In this case, if the company of cell phone has a monitored plug-in and inspect my memories, I would be annoyed. The same, the pictures in my phone are also my privacy. If you suspect that I've hidden terrorist information in my pictures, you could find what I've sent to others without inspecting my phone directly. It is my right to hide some secrets in my own cell phone, so I would not give up this to feel safe.

Why Are People Concerned About The Security of Their Secrets

In the time of the Mary Queen of Scots, people were confident with their encrypted messages and did not concern the privacy of their messages. However, for some time after that, people started to find a way to create more and more complicated ciphers, for the reason that they realized there are experts who could decipher their messages.

Why people suddenly concerned about this? Because in time of the Mary Queen of Scots, people did not know the existence of cipher experts who could decipher their codes. People were blind overconfident with their encrypted message to hide their secrets. However, there were experts showed out to deciphered their codes suddenly. Their privacy was threatened again and they could not hide their secrets if their ciphers were broken. To deal with this situation, they must create new kinds of ciphers to protect their secrets.

This is actually a phenomenon that cryptography is gradually formed at that time. It generated from some simple ciphers to hide some messages, then some people tried to decode the message and succeeded. To protect their privacy again, people who created ciphers put effort to improve the complicity of their ciphers with their creativity. Then people who decrypted ciphers learn more ways to make sure that they could decrypt more complicated ciphers. A virtuous cycle formed during this process that cipher makers and cryptanalysts improve themselves. Cryptography then improved as well.

The Vigenère cipher is a significant achievement in this process of improvement of cryptography. After hundreds of years of exploring, cipher makers this time created a cipher complicated enough to protect their secrets for a lifetime.

School or Prison - We are naked under monitoring

The most impressive passage for me is chapter 6. The author uses the dialogue between the Turk and Marcus to indicate the situation that citizens are under monitoring, through ways such as tracking their expense record. Marcus's thinking afterward during school strengthen this point.

"You think it's no big deal maybe? What is the problem with the government knowing when you buy coffee? Because it's one way they know where you are, where you been."

These words of the Turk straightly point out the security system of people in this country. The government can track an individual with their card record, when and where this person has purchased what can provide enough information to know his trend. This is not the only way, there are thousands of cameras in every block. As long as an individual show up in one of these cameras, the moving direction will be grasped and it is easy to use the series of cameras to track this person.

It goes without saying that the security system is useful to find out where a criminal suspect is. In the real world, this is an efficient way for the police to arrest suspects. However, the government can use the system not only find suspects but also monitor innocent citizens. The fact is that they do monitor what's happening in every corner of the country, even though there is nothing related to criminal issues.

After the conversation with the Turk, Marcus realized his naked situation during school. He intended to have a discussion about the privacy problem in the class but failed by the teacher. The scariest thing is that people are numb and be accustomed to their situation of being monitored, which means they know their privacy is violated but they do not care about this problem and ignore it.

In my opinion, it is appropriate to set the security system to protect the safety of citizens with a strict supervision. The government can request to see the expense record in bank or record in cameras only if there is enough evidence indicates that an individual is related to criminal issues. The supervise will be hard because the definition of a criminal suspect is blurry and the government is actually in charge of the whole system. I believe in the future we can find out an appropriate way to protect people's security without violated the whole citizens' privacy.

Mining Student Data - To protect students or invade students' life

In his essay, Michael Morris states that through mining student data, threat-assessment teams of universities have a great chance and plausible accuracy to predict possible violent behaviors with mining algorithms. As a result, it is responsible for every university to monitor students' academic record and prevent every possible tragedy.

Undoubtedly, in no way are we supposed to turn blind eyes to the fact that as the development of statistics and computer science, the mining algorithms is remarkable in this Internet era. Like the way Amazon know what productions we are interested in and may purchase and recommend them in our app,  threat-assessment teams are probably detected most of possible violent behaviors before they come true. So mining student data can be a effective way to prevent those terrible issues like suicide or criminal behaviors. 

However, the accuracy of the mining algorithms is not 100 percent, or even far less than 100 percent. As Micheal Morris said in his essay, I have had my credit-card transaction declined for many times since I created in China but lived in America now. The bank monitored my transaction record and defined it as an unusual pattern of spending America dollars with my credit card. My life was heavily infected during the time my card was freezing. The protection that bank provided actually based on the inaccurate result of the mining algorithm and it took the unnecessary action. The same as my bank, Amazon usually makes inaccurate prediction and recommendation as well, that's why our app often shows productions unrelated to our interests.

Similarly, the mining algorithms can lead threat-assessment teams to wrong direction and judge some nonviolent academic record as possible threat to campus safety. If a university take action according to that prediction and ask an innocent student to have a conversation, that will definitely affect the student's daily life. The feeling of being monitored and offended will come to the student and prevent them from concentrating on their career. In that case, the university just invade the student's life let alone by a way that even though the university does not take any action, it has already pried the student's privacy.

Under the situation that the algorithm can not reach 100 percent accuracy, universities which use the data-mining technology may invaded normal students' daily life. As a result, I disagree with the statement of Micheal Morris and consider that it is not time for universities to abuse the data-mining technology.

 

 

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