I don't think we need to duplicate the explanation at all but a link to it 
sounds good :-)


On 1 May 2014 08:56:20 Ayrx <notifications@github.com> wrote:

> > @@ -3,6 +3,9 @@
> >  Message Authentication Codes
> >  ============================
> > +While cryptography supports both the CMAC and HMAC algorithms, we strongly
> > +recommend that HMAC should be used unless you have a good reason otherwise.
>
> Yes, the [question](http://crypto.stackexchange.com/q/15721/2573) has an 
> excellent answer from Thomas.
>
> The answer mainly boils down to "HMAC was here first" though, the 
> performance differences will vary and I don't feel it's a good idea to 
> mention that especially without benchmarking.
>
> I could add more details about HMAC being an older and more widely used 
> algorithm with a link to that particular crypto.SE answer if you guys think 
> it's a good idea.
>
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