3Com 9000 manual Glossary, Module

GLOSSARY

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 integrate geographically distant disparate networks. Also called cell relay.

ATM Interface An ATM Interface Carrier Module with one or two daughter cards.

Module

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.

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 A 1-bit field in the ATM cell header that corresponds to the loss priority (CLP) 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.