basic qos shaping

[wilsmith1]

Hi,

what is the basic difference between,

bandwidth 256 and

shape average 256000

when it comes to basic qos shaping ?

[John Blakley]

With QoS, the bandwidth statement guarantees that 256k will be available to the class that you have applied it to. The shape statement shapes to 256k and doesn't allow it to go above that. The class that has the bandwidth statement is allowed to take up 100% of the link if there's no other traffic needing it.

[wilsmith1]

Thanks for the reply blakley,

if I am getting you right, the shape statement will not allow the particular traffic to take more than 256k, even the rest of the link's bandwidth is available. But the bandwidth statement is allowed to take the total link's bandwidth if thats available.

[Vasileios Bouloukos MSc, ITIL, CCIE]

Hi Wil,

Just to make clear that by configuring the bandwidth  command you do not mean just to apply this command under the intrface but it is part of QoS policy (e.g CBWFQ).

Otherwise the bandwidth command does not have any effect to QoS and is used for different purposes e.g. to affect the cost to a routing protocol e.g ospf

Hope that helps,

Vasilis