VLAN based QoS

Hi

I am configuring VLAN based QoS on a catalyst switch.

I have matched the traffic thus:

ip access-list extended HTTP
permit tcp any eq 80 any
!
class-map HTTP
match access-group name HTTP

and then I need to change the dscp value:

policy-map VLAN46
class HTTP
set dscp 16

and then apply:

interface vlan 46
service-policy input VLAN46

My question is that the solution provided has an additional line in the
class-map HTTP which reads:-

class class-default
trust dscp

is this strictly necessary to the solution ?
Thanks for reading!

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Received on Thu May 13 2010 - 11:57:45 ART