As mentioned previously, in the computing world it a bit challenging for us humans to prove the integrity of a message. We use hashing algorithms to assist us in determining the integrity of a message. In this section, we're going to take a look at the two main hashing algorithms being used today, which are MD5 and SHA:
Why do we need to validate the integrity of a message? Let's assume that there are two people, Bob and Alice. They would both like to communicate over a network. Alice wants to send Bob a message, but Bob is also concerned that the message may be altered before it arrives at his end. To help Bob determine if the message was altered during transmission or not, Alice would need to create a cryptographic hash of the message and send both the message and the hash values to Bob:
When Bob receives the message, Bob also creates a cryptographic...
