Re: encryption question

Rael wrote:
Thanks for the example.

I still am not sure what 'E' and 'A' are from your algorithm outline, and where they come from?

2. KE := HMAC(P,S + 'E')
3. KA := HMAC(P,S + 'A')

They are called KDF labels, and are just one way of ensuring that the encryption key and the MAC key aren't equal. Another common way is to generate one large key block and split it in halves.
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