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Hello,
I have just finished pouring through all the notes on Statistics and
have found no answer to my question. The question is:
If I am issuing the following command:
Show node4 BYLV24 line isa-0 all statistics, for every 00:10:00 until
15-jan-1992:15:00 duration 00:09:58
and the manual says that the following formula is being use
to calculate the multiple collision percentage:
mcfs *100% =CSMA/CD contention with multiple collision
----
fs
>>>>>>>>
>>>>>>>> The attribute "CSMA/CD Contention..." is not defined for a
>>>>>>>> Phase4 entity. So I presume you mean:
>>>>>>>> SHOW NODE bylv24 CSMACD STATION isa-0 ALL STATISTICS.
>>>>>>>>
a. Does MCC then take a sample at 00:00:00 minutes and then again at
00:09:58 minutes subtract the numbers (9:58min sample - 0min sample) and
then compute the statistic? Or does MCC poll, say every minute and compute
the statistic for every minute and then average it over the 9:58 minutes?
(By the way this was asked in note 1304 but never answered)
>>>>>>>>> Depends on whether the data is "current", that is, if it is
>>>>>>>>> obtained directly from the entity or "past", that is, gotten
>>>>>>>>> from the repository. In the former case two samples are
>>>>>>>>> gotten (one at the beginning of the period and the other at the
>>>>>>>>> end of the period) and statistics computed. In the later case
>>>>>>>>> there can be more than two samples during the period of interest
>>>>>>>>> and these are used to calculate the change in counter values
>>>>>>>>> over the requested duration and then statistics are computed
>>>>>>>>> for the entire duration, not for every pair of samples and then
>>>>>>>>> averaged.
b. Why do you only use Frames Sent(fs) and not a combination of frames Sent(fs)
and Multicast Frames sent(mfs) i.e. mcfs/(fs+mfs)? Or does the multiple
collision frames counter only count multiple collisions for non-multicast
frames?
>>>>>>>>> "fs" is the total number of frames(including multicast) successfully
>>>>>>>>> transmitted. This also includes frames transmitted after collisions
>>>>>>>>> on previous attempts.
Thanks in adance,
Julie Ann Lunt
Networks and Communications, Cologne Germany
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