Algorithm & Protocol Flashcards
Algorithm
Algorithms are used to encrypt and decrypt data. An algorithm is a formula that is used to turn plaintext (readable text) into ciphertext (unreadable text). The data goes through an algorithm and becomes encrypted. If it’s two way encryption, the encrypted data can be decrypted using a key or by putting the data back through the algorithm. However if the algorithm is a one-way (hash function) such as SHA (Secure Hash Algorithm), then it can’t be decrypted. AES (Advanced Encryption Standard) is an example of an algorithm. This algorithm is symmetric meaning it uses one key to both encrypt and decrypt the data. The problem with one key is that the key needs to be shared between the sender and receiver safely. Diffie-Hellman key exchange solves this problem by creating a shared key that cannot be found by watching the communication between the sender and receiver. This way, only the sender and receiver will know the secret shared key.
AES has a maximum of 256-bit with the lowest being 128-bit. Using higher bits also means that it will be slower to process. The more complex an algorithm is with more layers of procedure, the more secure the encryption is. Even the lowest AES encryption with a 128-bit cipher will take trillions of years to try every possible combination with current computing power. A good algorithm is an algorithm that has the most possible combinations as this means that decrypting it will take a very long time and so the encryption is very secure.
Protocol
A protocol ensures that websites are reliable and secure. Sites that transfer data between clients and web servers should encrypt the data so that people with malicious intent cannot access the data. SSL (Secure Socket Layer) is an example of a protocol. This protocol assures the user that the website is encrypted and is safe to use. Sites that have a padlock icon indicate that the site is safe and follows SSL protocols. To obtain a SSL certificate, the website will have to purchase from a Certificate Authority after they check if the website is secure. The SSL certificate provides the site with a public cryptographic key that is used to secure transfer of data over a network between the client and web server. An example of a site with SSL are bank sites. To view the amount of money you have, you’ll need to enter your bank details. If the bank site doesn’t follow protocols and have a SSL certificate, then anyone could view your bank account and other personal information that is sent to the site. However, if the bank site has SSL, this means that the connection is secure and private meaning that every data that is being transferred between you and the web server is private.
Protocols are necessary for strong security and it’s compulsory that they are followed so that information/data is encrypted and inaccessible to those who aren’t supposed to access it.
