66
TRAFFIC CLASSIFICATION, TP, AND LR
CONFIGURATION
When configuring traffic classification, TP, and LR, go to these section for
information you are interested in:
■ “Traffic Classification Overview” on page 861
■ “TP and LR Overview” on page 864
■ “Traffic Evaluation and Token Bucket” on page 864
■ “LR Configuration” on page 866
■ “Displaying and Maintaining LR” on page 867
Traffic Classification
Overview
Traffic Classification Traffic classification is to identify packets conforming to certain characters
according to certain rules. It is the basis and prerequisite for proving differentiated
services.
A traffic classification rule can use the precedence bits in the type of service (ToS)
field of the IP packet header to identify traffic with different precedence
characteristics. A traffic classification rule can also classify traffic according to the
traffic classification policy set by the network administrator, such as the
combination of source addresses, destination addresses, MAC addresses, IP
protocol or the port numbers of the applications. Traffic classification is generally
based on the information in the packet header and rarely based on the content of
the packet. The classification result is unlimited in range. They can be a small
range specified by a quintuplet (source address, source port number, protocol
number, destination address, and destination port number), or all the packets to a
certain network segment.
Generally, the precedence of bits in the ToS field of the packet header is set when
packets are classified on the network border. Thus, IP precedence can be used
directly as the classification criterion inside the network. Queue techniques can
also process packets differently according to IP precedence. The downstream
network can either accept the classification results of the upstream network or
re-classify the packets according to its own criterion.
The purpose of traffic classification is to provide differentiated services, so traffic
classification is significant only when it is associated with a certain traffic control or
resource assignment action. The specific traffic control action to be adopted
depends on the phase and the current load status. For example, when the packets
enter the network, TP is performed on the packets according to CIR; before the
packets flow out of the node, TS is performed on the packets; when congestion
To Next Page
Loading...
