QoS and CoS Features

Cisco EtherSwitch Service Modules Feature Guide

Information About the Cisco EtherSwitch Service Modules

•Kerberos security system to authenticate requests for network resources by using a trusted third party (requires the cryptographic versions of the Cisco EtherSwitch service module software image)

•802.1Q tunneling to allow customers with users at remote sites across a service provider network to keep VLANs segregated from other customers, and Layer 2 protocol tunneling to ensure that the customer network has complete STP, CDP, and VTP information about all users (available on the Cisco EtherSwitch service module but not on the integrated services router [ISR])

•Automatic QoS (auto-QoS) to simplify the deployment of existing QoS features by classifying traffic and configuring egress queues (voice over IP only).

•Cross-stack QoS for configuring QoS features on Cisco EtherSwitch service modules in a switch stack rather than on an individual Cisco EtherSwitch service module basis.

•Classification

–Classification on a physical interface or on a per-port per-VLAN basis.

–IP type-of-service/differentiated services code point (IP ToS/DSCP) and 802.1p CoS marking priorities on a per-port basis for protecting the performance of mission-critical applications.

–IP ToS/DSCP and 802.1p CoS marking based on flow-based packet classification (classification based on information in the MAC, IP, and TCP/UDP headers) for high-performance quality of service at the network edge, allowing for differentiated service levels for different types of network traffic and for prioritizing mission-critical traffic in the network.

–Trusted port states (CoS, DSCP, and IP precedence) within a QoS domain and with a port bordering another QoS domain.

–Trusted boundary for detecting the presence of a Cisco IP phone, trusting the CoS value received, and ensuring port security.

•Policing

–Policing on a physical interface or on a per-port per-VLAN basis.

–Traffic-policing policies on the Cisco EtherSwitch service module port for managing how much of the port bandwidth should be allocated to a specific traffic flow.

–Aggregate policing for policing traffic flows in aggregate to restrict specific applications or traffic flows to metered, predefined rates.

•Out-of-profile markdown for packets that exceed bandwidth utilization limits

•Ingress queueing and scheduling

–Two configurable ingress queues for user traffic (one queue can be the priority queue).

–Weighted tail drop (WTD) as the congestion-avoidance mechanism for managing the queue lengths and providing drop precedences for different traffic classifications.

–Shaped round robin (SRR) as the scheduling service for specifying the rate at which packets are dequeued to the stack internal ring (sharing is the only supported mode on ingress queues).

Cisco IOS Release 12.2(25)SEC