Re: I-D Action: draft-ietf-6man-default-iids-11.txt

[Fernando Gont <[e-mail]>]

On 05/16/2016 04:08 PM, Brian E Carpenter wrote:
> Hi Gengyu,
> 
>>> RID is not random or random identifier according to the context above.
>>>
>>> F() is an inreverse function, not a pseudorandom function.
> 
> I agree that this is incorrect use of terminology; an irreversible hash is
> not mathematically equivalent to a pseudo-random number generator. But the
> effect is the same: an attacker has no way to predict the next F(x) or to
> obtain the value of x. As far as practical engineering goes, F() can be treated
> as a random number. So I don't see why this invalidates the use of RFC 7217.
> 
> You could submit an erratum for RFC 7217 at http://www.rfc-editor.org/errata.php#reportnew
> so that the terminology can be corrected when the document is updated.

FWIW, the term "PRF" (as *opposed*) to PRNG was suggested by Alfred
Hoenes -- IIRC, a mathematician. IIRC, he noted that a hash function is
simply one possible way of a PRF.


-- 
Fernando Gont
SI6 Networks
e-mail: [e-mail]
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492