Carrier Access Broadmore 1750, Руководство пользователя

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Glossary-6 Broadmore 1750 - Release 4.6
Glossary
Glossary of Terms
ATM Adaptation Layer (AAL)
Type 1
AAL functions in support of constant bit rate, time-dependent traffic
such as voice or video (default in CES-CBR configuration).
Type 2
AAL undefined by International Standards bodies. Its anticipated use is
for variable bit rate video transmission.
Type 3/4
AAL functions in support of variable bit rate, delay-tolerant data traffic
requiring some sequencing and/or error detection support. This was
originally two AAL types, i.e., connection-oriented data traffic requiring
minimal sequencing or error detection support.
Type 5
AAL functions in support of variable bit rate, delay-tolerant connection-
oriented data traffic requiring minimal sequencing or error detection
support.
Broadband Bearer Capability
A bearer class field that is part of the initial address message.
BCOB
Broadband Connection Oriented Bearer -- information in the SETUP
message that indicates the type of service requested by the calling user.
BCOB-A
Bearer Class A -- indicated by ATM end user in SETUP message for
connection-oriented, constant bit rate service. The network may perform
internetworking based on AAL information element (default in CES-
CBR configuration).
BCOB-C
Bearer Class C -- indicated by ATM end user in SETUP message for
connection-oriented, variable bit rate service. The network may perform
internetworking based on AAL information element.
BCOB-X
Bearer Class X -- indicated by ATM end user in SETUP message for
ATM transport service where AAL, traffic type, and timing requirements
are transparent to the network.