Cisco Cisco Packet Data Gateway (PDG) Fehlerbehebungsanleitung
Intelligent Traffic Control
▀ How it Works
▄ Cisco ASR 5000 Series Enhanced Feature Configuration Guide
OL-22983-01
How it Works
ITC enables you to configure traffic policing on a per-subscriber/per-flow basis with the potential to manipulate
Differentiated Services Code Points (DSCPs), queue redirection (for example, move traffic to a Best Effort (BE)
classification), or drop profile traffic.
Differentiated Services Code Points (DSCPs), queue redirection (for example, move traffic to a Best Effort (BE)
classification), or drop profile traffic.
In flow-based traffic policies, policy modules interact with the system through a set of well defined entry points, provide
access to a stream of system events, and permit the defined policies to implement functions such as access control
decisions, QoS enforcement decisions, etc.
access to a stream of system events, and permit the defined policies to implement functions such as access control
decisions, QoS enforcement decisions, etc.
Traffic policing can be generally defined as
policy: condition >> action
condition: Specifies the flow-parameters like source-address, destination-address, source-port, destination-port,
protocol, etc. for ingress and/or egress packet.
action: Specifies a set of treatments for flow/packet when condition matches. Broadly these actions are based on:
Flow Classification: Each flow is classified separately on the basis of source-address, destination-
address, source-port, destination-port, protocol, etc. for ingress and/or egress packet. After
classification access-control allowed or denied by the system.
classification access-control allowed or denied by the system.
QoS Processing for individual flow and DSCP marking: Flow-based traffic policing is implemented by
each flow separately for the traffic-policing algorithm. Each flow has its own bucket (burst-size) along
with committed data rate and peak data rate. A Token Bucket Algorithm (a modified trTCM)
[RFC2698] is used to implement this flow-based QoS traffic policing feature.
with committed data rate and peak data rate. A Token Bucket Algorithm (a modified trTCM)
[RFC2698] is used to implement this flow-based QoS traffic policing feature.
Refer to the Traffic Policing and Shaping chapter for more information on Token Bucket Algorithm.