ASR9k BNG QOS policy config

[theo Bogatsu]

HI All

We have recently deployed a BNG on a Cisco ASR 9904 using ACS as the AAA server. Our subscribers will authenticate via the ACS using their mac address and they will be assigned to a group based on their bandwidth requirents/profile.

The challenge now is that we wouold like to offer some of our subcribers a best effort service with certain contention ratios for example we would like to have a 2Meg services with a contention ratio of 2. Could you please guide me on how we can go about configuring this?

[takao.nakamaru · Accepted solution]

If I understand correctly by contention ratio of 2, you wish for a DSLAM with 100 subscribers synchronized at 2Mbps to offer 100 aggregate traffic.

If this particular DSLAM is serviced by a specific VLAN / subinterface

- Shape the aggregate rate at 100 Mbps (by applying shaping on the VLAN subinterface)

- Shape individual subscriber sessions (by applying shaping on ppp session level) to ensure that the traffic is equally distributed among them

I am not sure about the syntax but you can try something like the following

interface Bundle-Etherxxxx.yyyy  !!!! DSLAM subinterface
 service-policy output AGGREGATE_100M subscriber-parent
 .....
 encapsulation dot1q yyy
!
 
policy-map AGGREGATE_100M
 class class-default
  shape average 100 mbps 
 !
!
policy-map SUBSCRIBER_20M
 class class-default
  shape average 20 mbps
 !
 end-policy-map
!

This applies if you can group similar subscribers in same VLAN. If this is not the case I have heard of a feature "shared-policy-instance" mentioned in this forum that you can also check out

https://supportforums.cisco.com/document/12378576/asr9k-bng-hqos-spi-single-user-multiple-sessions

[theo Bogatsu]

Thanks takao.nakamaru.