Understanding the hashing process
Ensuring data is not altered (modified) during transmission is very important, and to help us determine whether the integrity of a message is maintained, we can use hashing algorithms. Hashing algorithms are designed to take an input, such as a string of text or a file, and then use a one-way function to create a digest. The digest is a hash representation of the input and it cannot be reversed. Each unique file or message will generate a unique hash value (digest). This means that if the data is changed in any way, the hash value will be uniquely different.
The following diagram shows the one-way hashing process:
Figure 6.5 – Hashing process
How does this process work between devices? Imagine a sender, Host A, wants to send a message to a destination device, Host B. Rather than Host A sending the message as is, Host A will create a digest of the message. Once the digest has the message created, Host A will send both...
