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Glossary

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fixed-length cells permit processing to occur in the hardware. ATM is
designed to maximize the benefits of high-speed transmission media, such as
SONET, E3, and T3.

ATM ARP server

A device that supplies logical subnets running classical

IP over ATM with address-resolution services.

ATM endpoint

The initiating or terminating connection in an ATM

network. ATM endpoints include servers, workstations, ATM-to-LAN
switches, and ATM routers.

ATM Forum

The international organization founded jointly by Northern

Telecom, Sprint, Cisco Systems, and NET/ADAPTIVE in 1991 to develop
and promote standards-based implementation agreements for ATM tech-
nology. The ATM Forum broadens official standards developed by ANSI
and ITU-T and creates implementation agreements before official standards
are published.

ATM layer

A sublayer of the Data Link layer in an ATM network that is

service-independent. To create standard 53-byte ATM cells, the ATM layer
receives 48-byte segments from the AAL and attaches a 5-byte header to
each. These cells are then sent to the physical layer for transmission across
the physical medium.

See also: AAL.

ATMM

ATM Management: A procedure that runs on ATM switches,

managing rate enforcement and VCI translation.

See also: ATM.

ATM user-user connection

A connection made by the ATM layer to

supply communication between at least two ATM service users, such as
ATMM processes. These communications can be uni- or bidirectional, using
one or two VCCs, respectively. See also: ATM layer and ATMM.

ATP

AppleTalk Transaction Protocol: A transport-level protocol that

enables reliable transactions between two sockets, where one requests the
other to perform a given task and to report the results. ATP fastens the
request and response together, assuring a loss-free exchange of request-
response pairs.

attenuation

In communication, weakening or loss of signal energy, typi-

cally caused by distance.

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