Cbr Dsx/E1 Module Overview; Cbr Dsx Module - 3Com 3C63100-AC-C - PathBuilder S600 Bridge/router Reference Manual

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HAPTER ATH UILDER
CBR DSX/E1 Module
Overview
S600 M A
ODULE AND PPLICATION
Figure 45 PathBuilder S600 Ethernet Block Diagram
PathBuilder
S600
Ethernet
Input
The data does not move from memory from the time it is received till the time it is
segmented. This guarantees maximum performance of the system.
On the opposite side, cells are received from the DS3 UNI, or other ATM
n
module, side through the STX module.
The SAR then assembles the cells belonging to the connections specified for it
n
and the CPU is given confirmation for the cells that are assembled.
The bridge function of the CPU examines the packet header, removes the
n
encapsulations, and forwards the packet to the proper destination after
learning the address and updating the bridge table. For further information on
bridging, see "Bridging" later in this chapter.
The PathBuilder S600 supports two CBR modules: CBR DSX and CBR E1. These
modules are port or application modules for connecting devices such as PBXs
(Private Branch eXchanges), video codecs, DSU/CSUs, T1 multiplexers, and channel
banks for connection over an ATM WAN service.

CBR DSX Module

The CBR service module provides four or eight DSX DS1 ports for transit over an
ATM network. The DSX DS1 inputs can be either ESF or SF using B8ZS or AMI. The
received frame can be tunneled through the ATM network using DS1 unstructured
mode or broken up into its DS0 and AB signaling components using DS1
structured mode. The structured mode allows DS0 mid span drop and insert or
grooming.
Structured and unstructured modes comply with ATM Forum AF-SAA-0032.000.
This service maps the DS1 service through AAL1 adaptation layer over a CBR
virtual channel connection (VCC). The VCC is established as a permanent virtual
circuit (PVC) and mapped from the PathBuilder S600s ATM port to either another
PathBuilder WAN access switch or an ATM Forum circuit emulation compliant
device.
O
VERVIEW
VP.VC
Bridge
DS3
Function
MAC Address to VP.VC Map
VP.VC
02608C123456 = DS3, 0.35
PathBuilder
S600
DS3
ATM
Network
DS3
PathBuilder
S600