Cisco 10000 Series Configuration Manual page 820

Glossary
Bits per second. A standard measurement of digital transmission speeds.
bps
A logical group of permanent virtual circuits (PVCs) with one virtual interface connecting to a peer
bundle
system.
C
Committed access rate.
CAR
See constant bit rate.
CBR
See Class-based Weighted Fair Queuing.
CBWFQ
See Cisco Express Forwarding.
CEF
A policy map that defines one or more classes of traffic and the actions you want the router to take on
child policy
the traffic, just as non-hierarchical policy maps do. However, in hierarchical policy maps, child policies
are nested within a top-level parent policy, and then the parent policy is attached to the interface.
See committed information rate.
CIR
An advanced Layer 3 IP switching technology. Cisco express forwarding (CEF) optimizes network
Cisco express
forwarding performance and scalability for networks with large and dynamic traffic patterns such as the Internet,
on networks characterized by intensive Web-based applications, or interactive sessions.
Extends the standard weighted fair queuing (WFQ) functionality to provide support for user-defined
class-based
weighted fair traffic classes. For class-based weighted fair queuing (CBWFQ), you define traffic classes based on
queuing
match criteria including protocols, access control lists (ACLs), and input interfaces. Packets satisfying
the match criteria for a class constitute the traffic for that class. A queue is reserved for each class and
traffic belonging to a class is directed to the queue for that class. On the Cisco 10000 series router, the
CBWFQ feature allows a virtual access interface (VAI) to inherit the service policy of the virtual circuit
(VC) that the VAI uses.
A modular QoS CLI element that you can use to define traffic classification rules or criteria. Class maps
class maps
organize data packets into specific categories called classes that can, in turn, receive user-defined QoS
policies. The traffic class defines the classification rules for packets received on an interface.
The three most significant bits (the User Priority bits) of the 2-byte Tag Control Information field in
class of service
the IEEE 802.1p portion of a Layer 2 IEEE 802.1Q frame header. QoS uses the User Priority bits for
Layer 2 CoS information. IEEE 802.1p class of service-based packet matching and marking feature
enables the Cisco 10000 series router to interoperate with switches to deliver end-to-end QoS. The
IEEE 802.1p standard allows QoS to classify inbound Ethernet packets based on the value in the class
of service (CoS) field and to explicitly set the value in the CoS field of outbound packets.
The reserved bandwidth for the queue. The rate at which a Frame Relay network agrees to transfer
committed
information rate information under normal conditions, averaged over a minimum increment of time. Committed
information rate (CIR), measured in bits per second, is one of the key negotiated tariff metrics.
QoS class defined by the ATM Forum for ATM networks. Constant bit rate (CBR) is used for
constant bit rate
connections that depend on precise clocking to ensure undistorted delivery.
See class of service.
CoS
Cisco 10000 Series Router Quality of Service Configuration Guide
GL-2
OL-7433-09