[c-nsp] Hub-Spoke QoS

[Dale Shaw]

Hi,

On Sat, May 9, 2009 at 7:45 PM, Lala Lander <sshafi at gmail.com> wrote:
> How are you going to configure QoS/Policing/Shaper
> on hub site so it cannot overwhelm a DS3 or OC3 site with say like 100~200
> Mbps traffic? I am looking for your suggestions how you are dealing with
> link speed mismatches in WAN especially when I am dealing with OC12 and DS3
> links.

Disclaimer: I don't know much about ATM.

Are those links access tails into a provider MPLS network? Do you use
kind of tunneling? What router hardware/interfaces/encapsulation do
you have? Do you have QoS set up already?

Assuming it's a really simple network, here's a quick, generic and
completely untested example that I'm sure someone will find a problem
with! :-)

ip access-list extended SITE1
 permit ip any 10.1.0.0 0.0.0.255
!
ip access-list extended SITE2
 permit ip any 10.2.0.0 0.0.0.255
!
class-map SITE1
 match access-group name SITE1
!
class-map SITE2
 match access-group name SITE2
!
policy-map HUB
 class SITE1
  shape average 154400000
 class SITE2
  shape average 154400000
!
interface WanInterfaceX/X
 service-policy output HUB

Things get more complicated with tunnels, platform limitations/quirks,
incorporating existing QoS settings, multicast, and so on, but it's
still possible.

Have a look at the Hiearchical Queuing Framework (HQF) and per-tunnel
QoS in 12.4(22)T. I haven't played with it myself -- I've found some
12.4(22)T too flaky -- but it looks promising.

cheers,
Dale