Dxi Mode 1A - 3Com 3C63100-AC-C - PathBuilder S600 Bridge/router Reference Manual

Figure 61 PathBuilder S600 to ATM PVC
PathBuilder S600
QSIM
VP 0
In
Out
It is also important to select the proper traffic contract from the ATM
switch/service provider. This card should utilize a VBR or CBR circuit set at the
speed of the connected port. See Figure 62.
Figure 62 PathBuilder S600 Traffic Contract
PathBuilder S600
QSIM In
1 Mbps
VBR service will work, however the synchronous path will be subjected to possible
discards and delay.

DXI Mode 1A

DXI protocol frame is an HDLC LLC1 frame similar to PPP protocol. In terms of the
brouter, it is easier to implement DXI Protocol since it only requires the Brouter to
encapsulate the SDU.
The ATM Forum defines the DXI service in three modes: 1A, 1B, and 2. The
PathBuilder S600 supports Mode 1A, which includes the following features:
up to 1023 virtual connections
n
supports an AAL5 transit encapsulation
n
maximum DTE SDU size 9232 bytes
n
Uses 16-bit FCS
n
Figure 63 shows the application for DXI.
VC 50
ATM
VP 0 VC 50
CBR or VBR at
1 Mbps
Sustained Cell
1 Mbps
Rate
Application Overview
PathBuilder S600
VP 10 VC 45
VP 10
Out VC 45
In
97