Datasheet

Data Sheet
© 2008 Cisco Systems, Inc. All rights reserved. This document is Cisco Public Information. Page 10 of 20
Advanced QoS
The Cisco Modular QoS CLI provides a modular and highly extensible framework for
deploying QoS, by standardizing the CLI and semantics for QoS features across all platforms
that are supported by Cisco IOS Software.
Standard 802.1p class of service (CoS) and differentiated services code point (DSCP) field
classification are provided, using marking and reclassification on a per-packet basis by source
and destination IP address, source and destination MAC address, VLAN ID, or Layer 4
TCP/User Datagram Protocol (TCP/UDP) port number.
Cisco control-plane and data-plane QoS ACLs on all ports help ensure proper marking on a
per-packet basis.
Shaped Round Robin (SRR) scheduling helps ensure differential prioritization of packet flows
by intelligently servicing the queues.
Weighted Tail Drop (WTD) provides per QoS class congestion avoidance at the queues
before a disruption occurs.
Strict priority queuing helps ensure that the highest-priority packets are serviced ahead of all
other traffic.
Priority queue rate limiting provides optional protection against lower priority queue starvation.
Configurable control plane queue assignment allows service providers to assign control plane
traffic to specific egress queue.
Prioritization of control plane traffic enables service providers to set QoS markings globally for
CPU-generated traffic so these protocol packets will receive priority in the network.
There is no performance penalty for advanced QoS functions.
Advanced traffic control
Upstream and downstream traffic flows from the end station or the uplink are easily managed
using ingress policing and egress shaping.
Ingress policing provides bandwidth monitoring in increments as low as 8 kbps.
Ingress policing is provided based on CoS, VLAN ID, DSCP, and QoS ACLs (IP ACLs or
MAC ACLs) which can include source and destination IP address, source and destination
MAC address, Layer 4 TCP/UDP information, or any combination of these fields.
Egress Weighted Fair Queuing guarantees the Committed Information Rate (CIR) between
traffic flows and queues.
Egress shaping for each queue provides smooth traffic control of available bandwidth.
Egress port rate limiting allows the service provider to control the traffic rate that is transmitted
out of the port.
Network Security