Frame-relay Be question

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Aug 4th, 2007
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Hi, I am studing for the ONT test, I just want to know if I understand correctly how the Be works in Frame-relay (Traffic shaping)enviroments, next is the way I understood the topic:

BE creates a bigger bucket (BC+BE), this does not mean that the bucket is going to receive more tokens at each interval, it means that during periods of low traffic some tokens will remain in the bucket, then, at the beginning of the next interval there will be the previous tokens + the ones belonging to the actual interval in the bucket, if at this new interval the traffic increases, the bucket will be able to dispatch more tokens to increase the number of bits to send (no more than BC+BE), the next intervals will use only the BC bucket size until the next period of low traffic, then the bucket will retain a little more tokens due the BE extra size.

thanks in advance for any clarification on this matter.

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Overall Rating: 5 (2 ratings)
hardiklodhia Sat, 08/04/2007 - 20:22
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Excess Burst. The number of non-committed bits the router is allowed

to send above Bc if there is sufficient credit. The amount of Be

?credits? is derived from unused Bc credits in previous intervals. Be

defaults to zero bits.

There is no limit to how long Be can ?store? unused Bc credits. It is a common

misconception that Be can only store credits from the previous interval or the

previous second.

For more info :

may this will help.


Pavel Bykov Sun, 08/05/2007 - 03:37
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Beware that policing buckets has some differences from shaping buckets. Especially in dual-rate scenario.


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