Week 9 & 10

We are down to the last month of the term.Finally, we will be able to relax after four weeks. In the meantime, I had to finish this learning log as a partial requirement for this subject. For the past week, we have discussed about cryptography. Recently, I have learned that encryption has two types: the symmetric and the asymmetric. Symmetric encryption uses only one key which acts the job of both encrypting and decrypting.  On the other hand, asymmetric encryption uses two keys: one for encrypting and the other one for decrypting. The name somehow explains everything on how each type works. Imagine having a key which is symmetrically split into two and each half can do the job of one another. Because of this, you won't be needing the other half since one of them can do the task of both encryption and decryption. Now, think of splitting a key unevenly and assign a task for each. Let's say that the unique shape of each half corresponds to a unique job which they, and only they, can do respectively. Since both of the keys do not have the same shape; therefore, they also have different functions. This explains the concept of asymmetrical encryption. One half can do only the encryption part, and the other half can only do the decryption part. The history of cryptography spans from the ancient civilization up to present; from the Egyptian hieroglyphics to the modern cryptography methods such as RSA, Diffie-Hellman etc. One last thing that I wanted to point out is the terms that serve an important guidelines in encrypting messages. First if diffusion which means that the order of text should be scattered as much as possible. Next is the confusion which determines that the relevance of the plain text from the cipher text should be as confusing or random as it could be. Last is the permutation which suggests that the characters of the text should be rearranged effectively to provide more confusion.