Configuring Class of Service
You configure class of service (CoS) when you need to override the default packet forwarding behavior of a J Series or SRX Series device—especially in the three areas identified in Table 241.
Table 241: Reasons to Configure Class of Service (Cos)
Default Behavior to Override with CoS | CoS Configuration Area |
|---|---|
Packet classification—By default, the J Series or SRX Series device does not use behavior aggregate (BA) classifiers to classify packets. Packet classification applies to incoming traffic. | Classifiers |
Scheduling queues—By default, the J Series or SRX Series device has only two queues enabled. Scheduling queues apply to outgoing traffic. | Schedulers |
Packet headers—By default, the J Series or SRX Series device does not rewrite CoS bits in packet headers. Rewriting packet headers applies to outgoing traffic. | Rewrite rules |
You can use either J-Web Quick Configuration or a configuration editor to configure CoS. This chapter contains the following topics. For more information about CoS, see the JUNOS Class of Service Configuration Guide.
For information about which devices support the features documented in this chapter, see the JUNOS Software Feature Support Reference for SRX Series and J Series Devices.
This chapter contains the following topics:
- Before You Begin
- Configuring CoS (J-Web Procedure)
- Configuring CoS Components with a Configuration Editor
- Configuring Virtual Channels
- Configuring Adaptive Shaping for Frame Relay
- Classifying Frame Relay Traffic
- Rewriting Frame Relay Headers
- Configuring Strict-High Priority
- Configuring CoS for Tunnels
- Configuring Strict High Priority for Queuing with a Configuration Editor
- Configuring Large Delay Buffers with a Configuration Editor
- Applying an Ingress Interface Policer
- Configuring Simple Filters and Policers
- Configuring CoS Hierarchical Schedulers
- Verifying a CoS Configuration