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New Member

QoS question

iam working in a small ISP, well i have 10M as a bandwidth, i devided ADSL users to 5 groups, iam giving each group a spicific amount of the BW, well my problem is when one of the groups is full, and another one is free, the first one can't take from the other, i want to allow a full bw group to take from the other one if and olny if there is a free BW in the other one, can this be done ?


Re: QoS question

yes, this can be done with different QOS features.

What are you using at the moment? I believe you are not using a Diff service qos , correct?

CBWFQ is a good option, but it really depends in what type of traffic and the kind of priorization you need.

A good place to start:


if it does, please rate this post.


New Member

Re: QoS question

yes correct, iam not using Diff, iam using CBWFQ , but the problem that i think that i need to make conditions like to say if group A has rached its limit and group B still free, then take BW from there and lets keep 0.5M for the free group, actually i asked some seniors and they say this cant be done by cisco router, they said i need another device like Packeteer or BlueCoat to it, but i still that there is a way to do this using cisco routers

Re: QoS question


assuming you can differentiate the groups by IP address a sample config could look like this:

class-map match-all Group1

match ip address 101

class-map match-all Group2

match ip address 102

policy-map Divide10MB

class Group1

bandwidth percent 45

class Group2

bandwidth percent 45

interface Ethernet0

max-reservable 90

service-policy output Divide10MB

access-list 101 permit ip any

access-list 102 permit ip any

This way you can guarantee at least 45% to each group, but each group also can utilize the full 10MB in case no other traffic exists.

There can be up to 256 (?) classes per policy-map.

Hope this helps! Please rate all posts.

Regards, Martin

Re: QoS question


I'm quite surprise to hear such afirmation, because I'm still looking for thing CISCO cant do.

But again check the link and you'll see all QOS features cisco IOS can give you,

and again, yes it can be done.

the other reply has some nice line too!


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