Parameterized Qos - Cisco ASR 9000 Series Configuration Manual

Deploying the Quality of Service (QoS)
configure
policy-map type qos q_out
class class-default
end
// applying configuration through dynamic-template
configure
dynamic-template type ppp dynamic_policy
service-policy input q_in
service-policy output q_out
end

Parameterized QoS

Parameterized Quality of Service (PQoS) guarantees reliable performance of a network application by reserving
for it the required network bandwidth. In this case, the prioritization is based on the type of data being carried
by the packet.
In the standard QoS, the importance of a packet is based on the priority level that is defined for it. It is possible
that in once case a video packet and an asynchronous data transfer packet have the same priority level defined.
In such a case, the router gives equal importance to both packets. As a result, because of bandwidth conflict,
there can be video degradation.
On the other hand, in PQoS, packet importance is based on the characteristics or parameters of the data that
is carried by the packet. For example, it is possible to have PQoS provide dedicated bandwidth for video
packets. Even at times when heavy loads of asynchronous data traffic are introduced into the network, PQoS
guarantees that video packets have priority over other data streams that do not require real-time streaming.
Parameterized QoS has the ability to define, modify, or delete QoS policy-map based Vendor Specific Attributes
(VSAs). VSAs are downloaded through the RADIUS server. The attributes from the parameterized QoS
policies are filtered and passed on to the policy object library; the latter parses and translates them into policy
objects. The VSAs define a two-level hierarchical policy to be applied on the subscriber session. The format
of the QoS VSAs is:
AVPair: qos-policy-in=add-class(sub,<parent-class, child-class>,<action-list>)
AVPair: qos-policy-out=add-class(sub,<parent-class, child-class>,<action-list>)
AVPair: qos-policy-in=remove-class(sub,<parent-class, child-class>)
AVPair: qos-policy-out=remove-class(sub,<parent-class, child-class>)
where:
• "sub", is a constant string, signifies that the current policy on the subscriber is to be modified
• <class-list> gives the hierarchy of the class to be added or removed (i.e. parent-class, child-class)
• <action-list> gives the QoS actions to be applied under the class being added
For more information about QoS parameters and its syntax, see Parameterized QoS Syntax in the
Parameterized QoS Policy Through RADIUS, on page
When a parameterized QoS policy for a subscriber is downloaded from the RADIUS server for the first time,
the VSAs are used to build the policy from scratch. After the policy is applied on the subscriber, any new or
modified VSAs downloaded for that subscriber from the RADIUS server automatically modifies the already
applied policy.
For deploying a Parameterized QoS policy from the RADIUS server, see
Policy Through RADIUS, on page
OL-28375-03
// policy-map output direction
187.
Cisco ASR 9000 Series Aggregation Services Router Broadband Network Gateway Configuration Guide, Release
187.
Configuring Parameterized QoS
Parameterized QoS
Configuring
4.3.x
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