Re: FddiTime

["Camelot..Camelot..it's only a model" <[e-mail]>]

Dan,

   There have been some replies on the list (I can forward them to you)
regarding Anil's suggestion to change FDDItime in the SNMP MIB from 80
nanosecond units to 1 microsecond units.  The arguments against being the
desire for consistency between the SNMP and SMT MIBs with regards to units and
that any kind of conversion for a more understandable display format should
occur in the NMS.

   There was some concern that the signed 32 bit integer defined in SNMP would
restrict the range of values supported by SMT's unsigned 32 bit integer 
definition and that the switch to 1 microsecond units would overcome this
restriction.  After doing some quick math I came up with 2.86 minutes as a max
on a signed 32 bit integer in 80 nanosecond units.  Looking over SMT 7.1, it
looks like none of the MAC timers get even close to this value, which
leaves PORTMACLoopTime and SMTTrace-MaxExpiration as possible points of
contention.  PORTMACLoopTime does have its range explicitly stated in SMT 7.1
(2500000..4294967295 in 80 nanosecond units), but its status is optional so
it's likely to be dropped from the SNMP MIB.  SMTTrace-MaxExpiration has a
range greater than 6 seconds, but it's unlikely that a user would need to set
the value between 2.56 and 5.12 minutes.

   This leaves us with the original argument of making it easier for simple
NMS's and MIB compilers to return timer values in understandable units.

   - Larry Stefani
     Networks & Communications
     Digital Equipment Corporation