Dave,
Despite the potential value of CISC to FCP operation in
Class 3, we must advise against requiring or even recommending
it.
In our interoperability testing, we
have discovered there are devices with significant installed base that do
not behave properly when actually presented with CISC. Unfortunately, they
do not reject an N_Port Login that offers CISC, so this problem is not
discoverable.
Even
recommending CISC in a standard would therefore increase the incidence of
interoperability problems with use of Fibre Channel.
- Bob Nixon, Emulex alternate
representative
Howdy
All,
At the last FCP-4
working group meeting I presented a proposal to request the use of
continuously increasing SEQ_CNT (CISC) for Class 3 service.
While most believe
requiring continuously increasing SEQ_CNT for Class 3 service is a good idea,
one vendor indicated that none of their implementations support CISC, and
another vendor was concerned about the requirement.
As such, we have the
following options:
a. require CISC for
Class 3 service. This means that existing implementations can claim compliance
to a prior standard (e.g., FCP-3);
b. specify that CISC
should be used for Class 3 service;
c. no change (i.e.,
CISC is not required except for streamed Sequences).
My preference would
be option a.
What say
ye?
...Dave
(no disclaimer)