[comp.dcom.lans] Rate of change vs thresholds.

phil@shl.com (Phil Trubey) (06/27/91)

Here's a question for you network management gurus out there...

I'm wondering if there are any examples where you would want to monitor
the rate of change of some network variable rather than the absolute
value.  Eg. Typically people (or their network management stations)
monitor link utilization levels and want to be notified if the 
utilization rate ever hits a certain level (eg 60% or whatever
for an Ethernet network).  Have people found that there
are certain variables that they wished they could monitor the
rate of change of that variable (eg, how quickly the Ethernet
utilization level is changing)?

I'm just wondering if this is a useful feature or not.

Phil Trubey                     |  Internet: phil@shl.com  
SHL Systemhouse Inc.            |        or: phil%shl.com@uunet.uu.net
50 O'Connor St., Suite 501      |  UUCP:     ...!uunet!shl!phil
Ottawa, Ontario, Canada         |  Phone:    613-236-6604 x667
K1P 6L2                         |  Fax:      613-236-2043

jrd@cc.usu.edu (Joe R. Doupnik) (06/27/91)

In article <1991Jun26.190512.3937@shl.com>, phil@shl.com (Phil Trubey) writes:
> Here's a question for you network management gurus out there...
> 
> I'm wondering if there are any examples where you would want to monitor
> the rate of change of some network variable rather than the absolute
> value.  Eg. Typically people (or their network management stations)
> monitor link utilization levels and want to be notified if the 
> utilization rate ever hits a certain level (eg 60% or whatever
> for an Ethernet network).  Have people found that there
> are certain variables that they wished they could monitor the
> rate of change of that variable (eg, how quickly the Ethernet
> utilization level is changing)?
> 
> I'm just wondering if this is a useful feature or not.
> 
> Phil Trubey                     |  Internet: phil@shl.com  
> SHL Systemhouse Inc.            |        or: phil%shl.com@uunet.uu.net
> 50 O'Connor St., Suite 501      |  UUCP:     ...!uunet!shl!phil
> Ottawa, Ontario, Canada         |  Phone:    613-236-6604 x667
> K1P 6L2                         |  Fax:      613-236-2043
-----------------------------------
Phil,
	Yes, rates of change can be an important parameter: forstalling
disaster. But a program will have to do some fancy filtering to extract
meaningful results. The reason is, obviously, network activity is highly
irregular and not well described by simple random variable distribution
functions.
	Joe D.