Computationally Hard

1) Describe what it means for a problem to be “computationally hard.”
A problem is computationally hard if there is no algorithm to solve it and it must be done with brute force.
2) What strategies do people use to solve large computationally hard problems?
They often look for the best starting point which ,makes the rest slightly easier.
3) Why are computationally hard problems important in encryption strategies?
They are important because they make things and messages more secure because they are harder for computers to automatically decrypt.

Ciphers and random ciphers

• How much easier is it to crack a caesar cipher than a random substitution cipher? Can you put a number on it?
• It is so much easier. Probably 3 times easier.
• Was it difficult to crack a Random Substitution cipher? Did it take longer than you thought? shorter? Why?
• Yes it took longer and was more difficult. It was harder because I could not just shift the alphabet over to find out I had to figure out each letter individually. 
• Any encryption cipher is an algorithm for transforming plaintext into ciphertext. What about the other way around? Can you write out an algorithm for cracking a Caesar cipher? What about a random substitution cipher?
• Yes, it is possible to make an algorithm that shifts the alphabet until there becomes a recognizable message from the encrypted message. Same with the random substitution.  
• Recall that in RFC 3271, “The Internet is for Everyone” Vint Cerf wrote the following. What did he mean by “cryptographic technology?” What does it mean to you now?
• I think that he meant that there is a type of technology central to creating passwords and cracking them. It is along the lines of cybersecurity. It means now ensuring that the internet is safe. 

Blown to Bits Chapter 5 Reflection

• What is encryption?
• Encryption is the art of encoding messages so that they can’t be understood by eavesdroppers or adversaries into whose hands the messages might fall.
• What is cryptography? Provide an example.
• Cryptography is a form of “secret messages” that are encoded. A Caesar Cipher is a commonly known form of cryptography because it uses the rotation of the alphabet to encode messages.
• What is security through obscurity? Why is it bad?
• Security through obscurity is when companies create new “breakthrough” encryption methods, but refuse to open to the public. This is seem with high skepticism because most believe that if there was a new method then it should be open to the public to prove its security.
• What is the key agreement protocol? Why is it important to Internet commerce?
• The key agreement protocol is a one way computation which is a solution that can be found many different ways. For example 6*2=12 but 3*4=12 also. Same result but a different way of getting there. It is important because it allows for exchanges to happen with secret messages and public and private keys.
• What is a certificate? What role does it play in Internet security?
• A certificate is digitally authorized and signed key. This allows someone’s public key to be public and a message still accessed if someone has a certificate to access their private key.

Vigenere Cipher

From what you’ve seen what are the properties of the Vigenere Cipher that make it harder to crack? In other words, if you had to crack a vigenere cipher what would you do?

The main properties is that there is a key that is defined by the person who sent the message so the key can be very long and include a large variation of characters which mAkes it harder to crack the code. Not only that but the cipher does not just rotate the alphabet or assign a character per letter, it assigns letters based on the key. I would try to find the key or hack for the key.

Encryption

In your daily life what things do you or other people rely on keeping a secret? 
Who are these secrets being kept from? How are these things kept secret? 

People rely on personal information like social security number, bank account information, location, phone number, address, zip code, family members information, medical records, and insurance information like policy numbers to be kept secret. These secrets are being kept from people with malicious intent but also from the general public because privacy is a valued thing. These are kept with encoded information and also with things like firewalls that prevent attacks on a server or hacks. 

serr cvmmn va gur pnsrgrevn = free pizza in the cafeteria 

My birthday is tomorrow and I am turning sixteen years old. I cannot wait for this day to be over so it can be my birthday already. = Zl oveguqnl vf gbzbeebj naq V nz gheavat fvkgrra lrnef byq. V pnaabg jnvg sbe guvf qnl gb or bire fb vg pna or zl oveguqnl nyernql.

The Cost of Free

• This lesson is entitled The Cost of ‘Free.’ What does that mean to you now?
• That means the implications and consequences that come with having a free application that you reveal data on. 
• How would you explain The Cost of ‘Free’ to a family member, or person you just met, if you had only 60 seconds?
• Many websites and companies offer services that are free, whether you can download them for free in the app store or you can access it for free online. However, these companies such as Google and Facebook have increasingly high gains and profits. How do they make so much money while you receive their services for free? They sell your information and the data collected on you from your use of the application. They sell to the government or to private advertising organizations. All of the data on you can be found by other people and manipulated by malicious people. Therefore, there might be a big cost to your free applications. 
• Right now, which way are you leaning? Too little privacy? Right amount?
• Are you willing to give up some privacy (and potentially some security) to have free access to modern innovative tools - do you trust companies to be good stewards of your data?
• Are you concerned? Do you think too much of your data is out of your control? Do you think too much personally identifiable data is given over to someone else?
• What other questions do you have?

Implications of information

The idea that all information even the de-identified information can be either traced back to identified information or contained within a database that has identificable information. Also the notion that from de-identified information someone can get another person's voter information or access their personal information through a database is significant of how things are all connected and there is no way to have a completely secure presence on the internet.

Research yourself

Information:

• My blog for this class
• my blog from last 
• My profile picture from my google accounts
• a picture of me from the Sagamore
• My HackerEarth profile
• My Girls Who Code bio for my TA position 
• my prezis

Where you found it:

All of the information was from google search results either in images or in the first pages of all results.

The information above reveal what extracurriculares I participate in and when/where they are, what school I go to, what I look like.

All of this can be abused.