Cisco 10000 Series Configuration Manual page 251

Marking Traffic
To service the growing numbers of customers and their needs, service provider networks have become
more complex and often include both Layer 2 and Layer 3 network devices. With this continued growth,
service providers must quickly identify the packets streaming across the network and apply the
appropriate service behavior before sending them to their destinations.
A differentiated service (DiffServ) model enables you to classify packets based on traffic classes. In this
model, traffic marking allows you to partition your network into multiple priority levels or classes of
service. By marking traffic, other network devices along the forwarding path can quickly determine the
proper class of service (CoS) to apply to a traffic flow.
An important aspect of DiffServ is that the markings must be consistently interpreted from end-to-end.
All devices in the network path must understand the per-hop behavior to apply to a specific class of
traffic. If one of the routers in the path does not act appropriately, the overall service for a particular
packet might not be as desired.
This chapter describes the marking capabilities of the Cisco 10000 series router. It includes the following
topics:
QoS Packet Marking, page 7-2
•
IP Precedence Marking, page 7-4
•
IP Differentiated Services Code Point Marking, page 7-6
•
Class of Service Marking, page 7-10
•
QoS Group Marking, page 7-13
•
ATM Cell Loss Priority Marking, page 7-14
•
MPLS Experimental Marking, page 7-14
•
Discard-Class Marking, page 7-16
•
Class-Based Frame Relay DE Bit Marking, page 7-17
•
Marking and Policing Traffic, page 7-18
•
• Tunnel Header Marking, page 7-18
• Restrictions and Limitations for Marking, page 7-19
• Restrictions and Limitations for Marking, page 7-19
Interfaces Supporting Marking, page 7-20
•
Classification and Marking Design Guidelines, page 7-21
•
Recommended Values for Traffic Marking, page 7-21
•
Configuring Traffic Marking, page 7-22
•
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Cisco 10000 Series Router Quality of Service Configuration Guide
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