3Com CoreBuilder 9000, Руководство пользователя

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G
LOSSARY
451
G
LOSSARY
ASIC Application Specific Integrated Circuit, a chip designed for a particular
application. ASICs are built by connecting existing circuit building blocks
in new ways. Because the building blocks already exist in a library, it is
much easier to produce a new ASIC than to design a new chip from
scratch.
ATM Asynchronous Transfer Mode. A transfer method used for LAN and
WAN. ATM carries voice, video, and data at speeds up to 2.2 Gbps and
can intergrate geographicaly distant disparate networks. Also called cell
relay.
ATM Interface
Module
An ATM Interface Carrier Module with one or two daughter cards.
ATM Layer Processor The ATM Layer Processor prepares cell header information and manages
temporary cell storage.
backplane The main bus that carries data within a device.
carrier module The ATM Interface Module without daughter cards.
cell An ATM Layer protocol data unit (PDU) characterized by fixed, rather
than variable, length payloads. The standard ATM cell is 48 bytes of
payload with 5 bytes of header.
Cell Loss Priority
(CLP)
A 1-bit field in the ATM cell header that corresponds to the loss priority
of a cell. Lower priority (CLP = 1) cells can be discarded under a
congestion situation.
chassis The hardware housing unit for the CoreBuilder
®
9000.
CoreBuilder 9000
A high performance modular switching family, which runs on an ATM
or Ethernet backplane.
daughter card Can be either OC-3, OC-12, single-mode or multi-mode or UTP5. These
cards are attached to the ATM Interface Carrier Module, to make the
Interface Module complete.