Re: When do HMAC use less CPU power than Hash function in a MAC


Ulf Reiman wrote:
When do HMAC use less CPU power than Hash function, (if it does it)
assume HMAC (Data) when Data can be from 8 to 120 byte compared with
a MAC message usingt Hash(Source address, Data) and Source address can
be from 2 to 8 byte.

source address? why does that matter?

Two things

1. Go look up universal hashing

2. MAC with a known key != hash.

Tom

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