Alcatel Speed Touch 591s, Technical User'S Manual

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Speed Touch 591s Technical Practices GL-1
February 2001 90-8785-01
Glossary
AAL ATM adaptation layer
A layer that sits above the ATM layer and adapts non-ATM bit streams into
ATM cells.
AAL1 ATM adaptation layer - type 1
AAL1 is a specific type of ATM adaptation intended for constant bit rate
service applications.
AAL5 ATM adaptation layer - type 5
ACT absolute congestion threshold
ACT is a frame relay parameter related to the buffer capacity of a frame relay
device. At the ACT, the frame relay device discards all newly arriving
frames and raises a congestion alarm. See also MCT and SCT.
ADSL asymmetric digital subscriber line
AIS alarm indication signal
An AIS is a code sent downstream in a digital network to indicate that a
traffic-related defect has been detected. It is also known as an RAI or yellow
alarm.
AR access rate
The effective maximum bandwidth of a frame relay port
ASAM ATM subscriber access multiplexer