[nfsv4] Potential erratta for RFC7931

[David Noveck <[e-mail]>]

Based on the recent discussion that Bruce and I had, I'm thinking of filing
an erratta, replacing the following paragraph in section 5.8:


Note that the NFSv4.0 specification requires the server to make sure
that such verifiers are very

unlikely to be regenerated.Given that it is already highly unlikely
that the clientid4 XC

is duplicated by distinct servers, the probability that SCn is
duplicated as well has to be

considered vanishingly small.  Note also that the callback update
procedure can be

repeated multiple times to reduce the probability of further spurious matches.


With the following replacement:

Although the NFSv4.0 specification requires the server to make sure that
such verifiers are very unlikely to be regenerated, different servers may
use the same approach to the construction of such verifiers, raising the
probability that two distinct servers might inadvertently assign the same
verifier value. The fact that the servers in question have assigned the
same clientid4 may raise this probability.  In order to guard against the
possibility that such assignments might cause two distinct

servers to be incorrectly considered the same, the SETCLIENTID procedure
mentioned above needs to be repeated at least once.  This will ensure that
the sucessive confirm values SCn, SCn'. SCn'' generated by these repeated
SETCLIENTID operations cannot all collide with a verifier previously
received by the client when communicating with IPn.

Comments?