RE: dot1dStpPortPathCost32

I'm not very knowledgeable about the new object, but I think the
support should be conditionally mandatory, and the condition should
spell out that one or the other should be used.

An alternative would be to have different compliance caluses, one to
support the older compliance rules and another to support the new
compliance rules, but if there's only one object that would be
mandatory in the new clause, that doesn't seem worth it.

dbh
 

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Les Bell
Sent: Tuesday, November 02, 2004 4:50 AM
To: [email protected]
Cc: [email protected]
Subject: Re: [Bridge-mib] dot1dStpPortPathCost32




Use of the 32-bit path cost was defined in both 802.1w (RSTP) and
802.1t.
802.1t was a collection of enhacements to Bridges, including those
that support legacy STP.  So the 32-bit path costs do not just apply
to RSTP.

I think you are right that dot1dStpPortPathCost32 should be
conditionally mandatory, but for any Spanning Tree implementation that
supports 32-bit path costs, not just for RSTP.

Implementations that support 32-bit path costs should not use the
16-bit path cost object, dot1dStpPortPathCost, but I am not sure what
is the best way to deal with this.  Are we allowed to allocate a
special value to indicate it is not in use?  I think it would be safer
to return an SNMP error indicating the old object is not supported.

Les...





Juergen Schoenwaelder <[email protected]>@ietf.org on
22/10/2004
12:05:23

Please respond to [email protected]

Sent by:  [email protected]


To:   [email protected]
cc:
Subject:  [Bridge-mib] dot1dStpPortPathCost32


The revised BRIDGE-MIB adds dot1dStpPortPathCost32 and makes it
mandatory. I think this is broken since existing deployed
implementations won't support that object and thus are not compliant.
Can someone please explain in which situations the increased range of
dot1dStpPortPathCost32 is actually needed?
Is this only relevant for rapid spanning tree? In that case, I think
the object should be conditionally mandatory for boxes that do rapid
spanning tree and the old one stays current, probably with a special
value to use in case dot1dStpPortPathCost32 actually has the larger
path cost.

Please give advise.

/js

--
Juergen Schoenwaelder             International University Bremen
<http://www.eecs.iu-bremen.de/>        P.O. Box 750 561, 28725 Bremen,
Germany

_______________________________________________
Bridge-mib mailing list
[email protected]
 https://www1.ietf.org/mailman/listinfo/bridge-mib





_______________________________________________
Bridge-mib mailing list
[email protected]
https://www1.ietf.org/mailman/listinfo/bridge-mib