Function Summary - Extreme Networks BlackDiamond 6800 Installation And User Manual

— Ingress and egress rate shaping and limiting
— IEEE 802.1p VLAN priorities
— Weighted RED (WRED) congestion avoidance algorithm
— Assured Forwarding and Expedited Forwarding RFCs
• Service provider specific features, such as:
— Flexible remapping of DiffServ codepoints
— Flexible remapping of IEEE 802.1Q VLAN IDs
— VLAN tunneling via nested 802.1Q tags

Function Summary

The following sections provide brief descriptions of the key functions provided by the
ATM module. Each of these sections is expanded into greater detail in Chapter 3.
Asynchronous Transfer Mode (ATM)
ATM is a connection-oriented packet transmission technique that is widely used in
existing telecommunications networks to transport voice, video, and data. ATM uses
fixed size data packets called "cells" which are 53-bytes long and have a header that
includes a connection identifier. The connection identifier makes it possible to support
more than one point-to-point connection on a single physical ATM connection. The
switches in an ATM network use the connection identifier in each cell to forward the
cell to the next hop.
Synchronous Optical Network (SONET) and
Synchronous Digital Hierarchy (SDH)
SONET and SDH are the two terms used to identify a time division multiplexing
technology that is optimized for transporting voice traffic across a digital optical
network, but that is also capable of providing high-speed capacity for transporting data.
The term SONET is used to identify the technology used within the North American
digital network. Its standards are published by Bellcore and the American National
Standards Institute (ANSI). The term SDH is used to identify the equivalent standard
approved by the International Telecommunication Union (ITU) for use in Europe and
elsewhere in the global digital network. Because SDH evolved out of SONET, the two
standards are closely related and have been widely accepted as a dominant choice for
implementations requiring high transport capacity and resistance to failure. The term
Asynchronous Transfer Mode (ATM) Module Installation and User Guide
About the ATM Module
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