GL-1
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
G L O S S A R Y
A
AAA
authentication, authorization, and accounting (pronounced “triple a”).
AAL5
See ATM adaptation layer 5.
ABR
See available bit rate.
ADSL
See asymmetric digital subscriber line.
anonymous link
A link that does not provide a PPP username or endpoint. Multilink PPP (MLP) combines all of the
anonymous links into a single bundle called an anonymous bundle or default bundle.
asymmetric digital
subscriber line
A digital subscriber line (DSL) technology in which the transmission of data from server to client is
much faster than the transmission from the client to the server.
Asynchronous
Transfer Mode
International standard for cell relay in which multiple service types (such as voice, video, or data) are
conveyed in fixed-length cells. Fixed-length cells allow cell processing to occur in hardware, thereby
reducing transit delays. ATM is designed to take advantage of high-speed transmission media such as
E3, SONET, and T3.
ATM adaptation
layer 5
This layer maps higher layer user data into ATM cells, making the data suitable for transport through
the ATM network.
available bit rate
QoS class defined by the ATM Forum for ATM networks. ABR is used for connections that do not
require timing relationships between source and destination. ABR provides no guarantees in terms of
cell loss or delay, providing only best-effort service. Traffic sources adjust their transmission rates in
response to information they receive describing the status of the network and its capability to
successfully deliver data.
ATM
See Asynchronous Transfer Mode.
B
bandwidth
The range of frequencies a transmission line or channel can carry. The greater the bandwidth, the
greater the information-carrying capacity of a channel. For a digital channel this is defined in bits. For
an analog channel it is dependent on the type and method of modulation used to encode the data.
BGP
See Border Gateway Protocol.
Border Gateway
Protocol
Interdomain routing protocol that exchanges reachability information with other BGP systems. It is
defined in RFC 1163.