Frame Relay Mode - 3Com SuperStack II PathBuilder S330 Reference Manual

246 A B: P B
PPENDIX ATH UILDER
S330/S310 M A
ODULE AND

Frame Relay Mode

Frame relay mode is used to terminate a frame relay router, across the ATM
network, for example. This protocol mode converts the frame relay DLCI to a
VP/VC ATM connection.
A PathBuilder S330/S310 switch provides two interworking features to
interconnect a Frame relay network with an ATM network:
Service Interworking
Network Interworking
These interworking features are described in FRF.8 and FRF.5 respectively. The
major difference between these two features is that there is no FR-SSCS function
required for Service Interworking.
The following sections describe the details of these two interworking functions as
well as the features provided by the PathBuilder S330/S310 switch.
Service Interworking Function
Figure 177 shows a PathBuilder S330/S310 switch providing Service Interworking
function between Frame Relay and ATM services. In this setup, a Frame Relay DTE
communicates with an ATM DTE, regardless of the fact that there is a different
type of DTE at each end of the connection.
Figure 177 Frame Relay/ATM Service Interworking Connection (FRF.8)
LAPD Frames
Frame
Relay DTE
Frame
Frame
Relay
Relay DTE
Network
Application
Q.922
DL Core
PHY
O
PPLICATION VERVIEW
PathBuilder
S330/S310
Application
Null SSCS
Q.922
AAL 5
DL Core
SAR
ATM
PHY PHY
ATM
Cells
ATM
Network
Q.922
DL Core
PHY
ATM
DTE
Application
Null SSCS
AAL 5
SAR
ATM
PHY