80
C
HAPTER
4: P
ATH
B
UILDER
S600 M
ODULE
AND
A
PPLICATION
O
VERVIEW
Figure 45
PathBuilder S600 Ethernet Block Diagram
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.
n
On the opposite side, cells are received from the DS3 UNI, or other ATM
module, side through the STX module.
n
The SAR then assembles the cells belonging to the connections specified for it
and the CPU is given confirmation for the cells that are assembled.
n
The bridge function of the CPU examines the packet header, removes the
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.
CBR DSX/E1 Module
Overview
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.
ATM
Network
PathBuilder
S600
Ethernet
Input
Bridge
Function
PathBuilder
S600
DS3
DS3
VP.VC
MAC Address to VP.VC Map
02608C123456 = DS3, 0.35
VP.VC
PathBuilder
S600
PathBuilder S600
PathBuilder S600
DS3
Summary of Contents for 3C63100-AC-C - PathBuilder S600...
Page 8: ...INDEX 3COM CORPORATION LIMITED WARRANTY ...
Page 14: ...xiv CHAPTER SUPPLEMENTARY REGULATORY INFORMATION ...
Page 18: ...18 ABOUT THIS GUIDE ...
Page 28: ...28 CHAPTER 1 SYSTEM DESCRIPTION ...
Page 74: ...74 CHAPTER 3 GETTING STARTED ...
Page 230: ...230 INDEX ...