CHAPTER
Frame Relay to ATM Network and Service Interworking 12-1
12
Frame Relay to ATM Network
and Service Interworking
This chapter describes Frame Relay to ATM interworking. Frame Relay to ATM Interworking
allows users to retain their existing Frame Relay services, and as their needs expand, migrate to the
higher bandwidth capabilities provided by BPX switch ATM networks.
This chapter contains the following:
• Service Interworking
• Networking Interworking
• ATM Protocol Stack
• AIT/BTM Interworking and the ATM Protocol Stack
• AIT/BTM Control Mapping, Frames and Cells
• Management, OAM Cells
• Functional Description
• Management
Frame Relay to ATM Interworking enables frame relay traffic to be connected across high-speed
ATM trunks using ATM standard Network and Service Interworking (see Figure 12-1 and
Figure 12-2).
Two types of Frame Relay to ATM interworking are supported, Network Interworking and Service
Interworking. The Network Interworking function is performed by the AIT card on the IPX switch
and by the BTM card on the IGX switch. The FRSM card on the MGX 8220 supports both Network
and Service Interworking. See Figure 12-3 for some examples of ATM to Frame Relay Interworking.
