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Traffic shaping combined with queuing

Without any traffic shaping, queuing(ex: priority or custom) is only invoked when congestion occurs... correct?

When FRTS shaping is used and custom queuing also specified, is the queuing only invoked when traffic exceeds the shaped speed, or is it always used? ie: If no other traffic present, would traffic specified to use only 50% of shaped bandwidth use 100% of the shaped bandwidth?

When GTS is used with a GROUP specifing an ACL, is matching traffic always limited to the shaped amount, even if no other traffic on the line? Could non-shaped traffic dominate the line or is GTS-shaped traffic guaranteed the minimum amount?


Re: Traffic shaping combined with queuing

1. when you have traffic shapping and the limit

for the shaped value is exeeeded, all traffic arriving at the interface with

no token in the token bucket is queued using the configured queue to thier appropriate queue..

hence any type of queueing is not invoken unless some sort of trafiic conjestion exist either

via shapping or otherwise.

2. If you have a granular shaping instruction per protocol per bandwidth. The traffic over

its shapped value would be queued and sent at maximun shape rate configured. ( that's one of the uses of shaping, to trim rate at which

a specific traffic is sent). If its just queuing that is enable not shaping, then

a traffic for a specific queue can use as much bandwidth as availabel when there is no other traffic, hence no congestion.

3. if you have shaped and non-shaped traffic on an interface using GTS, the shaped traffic can use as much bandwidht as the maximum of the shaped

value while not-shaped traffic will also use bandwidht on as see bandwidth without the need to be controlled, however non-shaped traffic will use

all the bandwidht it needs till the interface start droping packet but the shaped traffic would be queued till there is enough token to start outputing

from that queue. if the there are non-shaped traffic, it could be possible that they may overwelm the interface

and prevent even shaped traffic from geting enough bandwidht to the shaped value.