CoS on Enhanced IQ PICs Overview
The Enhanced IQ (IQE) PIC family supports a series of non-channelized and channelized interfaces that run at a large variety of speeds. Sophisticated Class-of-Service (CoS) techniques are available for the IQE PICs at the channel level. These techniques include policing based on type-of-service (ToS) bits, five priority levels, two shaping rates (the guaranteed rate and shaping rate), a shared scheduling option, DiffServ code point (DSCP) rewrite on egress, and configurable delay buffers for queuing. All of these features, with numerous examples, are discussed in this chapter. For a comparison of the capabilities of IQE PICs with other types of PICs, see CoS Features and Limitations on M Series and T Series Routers.
For information about CoS components that apply generally to all interfaces, see Understanding How Class of Service Manages Congestion and Controls Service Levels in the Network. For general information about configuring interfaces, see the Junos OS Network Interfaces Library for Routing Devices.
IQE PICs can be used in Juniper Networks M40e, M120, M320 Multiservice Edge Routers and T Series Core Routers to supply enhanced CoS capabilities for edge aggregation. The same interface configuration syntax is used for basic configuration, and other CoS statements are applied at channel levels. Some configuration statements are available only in Junos OS Release 9.3 and later, as noted in this chapter.