Configuring CoS Hierarchical Schedulers

In metro Ethernet environments, a VLAN typically corresponds to a customer premises equipment (CPE) device and the VLANs are identified by an inner VLAN tag on Ethernet frames (called the customer VLAN, or C-VLAN, tag). A set of VLANs can be grouped at the DSL access multiplexer (DSLAM) and identified by using the same outer VLAN tag (called the service VLAN, or S-VLAN, tag). The service VLANs are typically gathered at the Broadband Remote Access Server (B-RAS) level. Hierarchical schedulers let you provide shaping and scheduling at the service VLAN level as well as other levels, such as the physical interface. In other words, you can group a set of logical interfaces and then apply scheduling and shaping parameters to the logical interface set as well as other levels.

This chapter discusses the following topics:

• Configuring Hierarchical Schedulers for CoS
• Hierarchical Schedulers Terminology
• Packet Handling in MX-series Routers
• Configuring an Interface Set
• Applying an Interface Set
• Interface Set Caveats
• Introduction to Hierarchical Schedulers
• Scheduler Hierarchy Example
• Controlling Remaining Traffic
• Internal Scheduler Nodes
• PIR-Only and CIR Mode
• Priority Propagation

Copyright © 2008, Juniper Networks, Inc. All rights reserved. Trademark Notice.