Packet Authentication

Packet authentication is used for two purposes:

  • To provide data origin authentication

  • To detect packets that have been tampered with

The following sections will discuss how packet authentication works (implementation), examples of functions that are used with packet authentication, the uses of packet authentication, and issues with performing packet authentication.

Packet Authentication Implementation

Hashing functions are used to create a digital signature by taking a variable-length input, such as user data or a packet, along with a key and feeding it into a hashing function. The output is a fixed-length result. If the same input is fed into the hashing function, it will always result in the same output.

Hashing Message ...

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