Datasheet

Data Sheet
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QoS
Advanced QoS
The VBS offers industry-leading mechanisms for marking, classification, and scheduling to
deliver superior performance for data, voice, and video traffic, all at wire speed.
Following are some of the QoS features supported:
●
Wire-rate performance supports highly granular QoS functions (for example, granular rate
limiting).
●
Cross-switch QoS allows QoS to be configured across the entire VBS.
●
IEEE 802.1p class of service (CoS) and differentiated services code point (DSCP) field
classification is provided, using marking and reclassification on a per-packet basis by source
and destination IP address, MAC address, or Layer 4 TCP or User Datagram Protocol (UDP)
port number.
●
Cisco control plane and data plane QoS ACLs on all ports help ensure proper marking on a
per-packet basis.
●
Four egress queues per port help enable differentiated management of up to four traffic
types.
●
Shaped Round Robin (SRR) scheduling helps ensure differential prioritization of packet flows
by intelligently servicing the ingress queues and egress queues.
●
Weighted Tail Drop (WTD) provides congestion avoidance at the ingress and egress queues
before a disruption occurs.
●
Strict priority queuing helps ensure that the highest-priority packets are serviced ahead of all
other traffic.
●
The committed information rate (CIR) function provides bandwidth in increments as low as 8
Kbps.
●
Rate limiting is provided based on source and destination IP address, source and destination
MAC address, Layer 4 TCP and UDP information, or any combination of these fields, using
QoS ACLs (IP ACLs or MAC ACLs), class maps, and policy maps.
●
Up to 64 aggregate or individual policers are available.