Cat 3550 stormcontrol

[hhermansen]

Does the stormcontrol feature in 3550 assume a fixed packet size or does it just count the number of bytes in the 1 sec interval ?

Regards

Herman

[murabi]

The storm control is based on the 1 sec interval.

Storm control (or traffic suppression) monitors incoming traffic statistics over a time period and compares the measurement with a predefined suppression level threshold. The threshold represents the percentage of the total available bandwidth of the port. The switch supports separate storm control thresholds for broadcast, multicast, and unicast traffic. If the threshold of a traffic type is reached, further traffic of that type is suppressed until the incoming traffic falls below the threshold level.

[hhermansen]

What about the packet size ? If, as I suspect, the stormcontrol feature assumes a packet size of 64 bytes, then the total percentage will be ten times higher with 640 bytes packet size. Why do I suspect that there is a default packet size: My experience is that that suppress limit is unpredictable. If you do show storm-control on a 2600 router then the output is like this

"Storm control:broadcast multicast unicast threshold 25 with default packet-size 64". I suspect that the implementataion on the 3550 also assumes a default packet size, even if the show storm-control output is different (doesnt say packet size).

Regards

Herman