gtpg1m0aGeneral Information

TPF System Application Types

The TPF system can be used by applications in many different ways, for example, as a transaction processing system, a network switch, a front-end processor, or all three types at once. Some application programs that work with the TPF system are:

Applications for the TPF system can be written in IBM C/370 language or in IBM High Level Assembler/MVS & VM & VSE language.

Transaction Processing

Figure 2 shows the use of the TPF central processing complex (CPC) in a transaction processing application. After a message arrives from the network, it is processed by the TPF system, the database is updated, and a message is sent back to the originator of the incoming message. Transaction processing with the TPF system provides high throughput, quick response time, high availability, and low cost per transaction.

Figure 2. Transaction Processing Application


Network Switching

Figure 3 shows how the TPF system is used in a network switching application. This TPF CPC has communication links to other transaction processing systems. An ATM, attached to CPC 1 in Processing Center A, sends a request to CPC 0, the TPF network switch. Using the routing database, TPF switches the request to CPC 2 in Processing Center B. Then, CPC 2 sends a reply through the TPF system, back to the originating ATM. Usually, network switches must distribute messages across many communication lines to many processing centers. Network switching with the TPF system provides rapid routing of messages over communication lines to many different processing centers.

Figure 3. Network Switching Application


Front-End Processing

Figure 4 shows a TPF front-end processor application. The advantage of a front-end processor is that it can be programmed to provide temporary services through stand-in applications if the appropriate back-end processor is not available. For example, a credit card check can usually involve looking up the credit limit and existing balances on a database belonging to one of the back-end systems. However, if that system is unavailable, the TPF front-end system can be designed to provide minimal credit checks so business can continue.

Figure 4 also shows separate systems with different applications connected to a TPF front-end processor. The front-end processor can direct messages received from the network to the appropriate application processor. The replies from the back-end transaction processors are transmitted back through the TPF system to the source of the message. If the processing center grows, additional back-end processors can be added. Environments that typically use front-end processors include the banking and securities industries as well as some large airline reservation systems.

Front-end processing with the TPF system provides:

Figure 4. Front-End Processor Application