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QOS-question in WRED when apply it to class-map with bw gurantee

hi all,

assume i have a class-map zzzz

and i have gurantee bw 10 %


assume i let it use wred in that class-map

the question is :

if  this class-map exsceedted the guranteeed vlaues of 10% of bw ,  will it be treadted with WRED ??


it will be treadted with WRED ,  when the congestions occurs on the interfacce as total ??


Super Bronze

Re: QOS-question in WRED when apply it to class-map with bw gura


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As you ask the questions, neither really.

What happens (assuming we're working with an ISR), an interface FIFO queue "overflows" into the policy-map.  If the overflow packets fall into any class queues with WRED defined, then those packets, as they are to be added to the class are subject to the WRED policy. Bandwidth defined for the class has no impact beyond perhaps how many packets are already in the class queue(s), which WRED takes into account when computing average overall class queue depth.  Interface congestion's impact is none of the foregoing can happen until the interface congests, but WRED only "cares" about the class packets it applied too.  I.e. a particular class could be empty while the interface is filling another class or classes.

Community Member

Re: QOS-question in WRED when apply it to class-map with bw gura

hi ,

so ,

the answer is<< there will be drop whatever therer were a gurantee bw >> . because i will be treated with WRED .

this is wt i understood , plz correct me if im wrong

another question:

if i didnt configure WRED on that class map ,

what will haapped when there is congestion on the interface  and the 10% bandwidth exceeded in that predefined class-map

what router will do ?

will  it use WRED ? or another thing ??

and what is the default behaviuor on router classpmaps when congestion occurs  ???


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