policy-map definition of shape average and service-policy

[getaway51]

Hi,

For config below applied to WAN interafce , may I know wht is the bandwidth applied to this policy?

Wht is the meaning of 'shape average 10000000'?

How is 'shape average 10000000' affected by  'service-policy qos-200'?

Which will decide the bandwidth or qos applied to the traffic>?

policy-map shaping-10
class class-default
shape average 10000000
service-policy qos-200

[Georg Pauwen]

Hello,

'shape average' just means that all traffic (class default) going out through the WAN interface is 'shaped' to 10MB. The value itself does not necessarily mean that the actual bandwidth available on your WAN is 10MB. 

Shaping , compared to policing, is usually a better way to limit traffic. Policing basically cuts off the traffic once the limit has been reached, while shaping snoothes the traffic out and allows for traffic bursts...that's the short explanation.

[Joseph W. Doherty]

"For config below applied to WAN interafce , may I know wht is the bandwidth applied to this policy?"

Cannot determine, as you didn't list the subordinate policy, qos=200. Additionally, you didn't list the interface etiher.

Depends on the policies, the interface and the nature of the traffic.
"Wht is the meaning of 'shape average 10000000'?"

Restrict bandwidth consumption to 10 Mbps. If actual bandwidth exceeds that, queue excess so that the average transmission rate doesn't exceed 10 Mbps. NB: if the "offered" rate continues to exceeds the shaped rate, the shaped queue will continue to fill until if overflows. Overflow is loss.

"How is 'shape average 10000000' affected by 'service-policy qos-200'?"

It's usually not. Normally, the queued traffic is dequeued by the subordinate policy, and the overall parent policy shaped rate is enforced.