3Com SuperStack II PathBuilder S330 Reference Manual page 250

242 A B: P B
PPENDIX ATH UILDER
S330/S310 M A
ODULE AND PPLICATION
The DXI protocol itself is based on HDLC and provides the mapping within the
HDLC frame to place the router data on an appropriate VC. (See Figure 172.)
Figure 172 DXI Protocol Enabling Transmission Between ATM Network and DXI Device
IP
Internet Router
DXI
DXI Link
Transport
Router/DXI
The ATM DXI Specification defines 3 different modes (1a, 1b, and 2) of
connections. This software release supports mode 1a, which includes the
following features:
Up to 1023 virtual connections
Uses AAL5
Maximum DTE SDU size: 9232 bytes
Uses 16-bit FCS
Through ATM DXI, the DCE allows the DTE to participate in an ATM network. (See
Figure 173.)
O
VERVIEW
Synchronous
V.35
RS 449/422, X.21, RS-530
DXI
Protocol
DXI Link
DS1
AAL 5
ATM Cell
Path Layer
Line Layer
Section Layer
Photonic Layer
ATM/DSU/SONET
DXI
Transport
A TM
SONET