High-speed connector
The high-speed connector is a generic transport mechanism for z/TPF applications to send user-defined messages or HTTP client requests to a server in an efficient way. You can use the high-speed connector to exchange messages between the z/TPF system and a local server farm or any server that supports TCP/IP.
- tpf_send_message
- Sends a synchronous request to a remote server where the ECB that calls the tpf_send_message function is suspended until the response is received or an error occurs. With the tpf_send_message function, z/TPF applications can also send a message to an endpoint and optionally receive a response.
- tpf_send_async_message
- Sends an asynchronous request to a remote server and returns control to the ECB that called the tpf_send_async_message function after the request is sent. A z/TPF application is entered in a new ECB when the response is received or an error occurs.
- tpf_httpSendRequest
- Sends a synchronous HTTP request to a remote server where the ECB that calls the tpf_httpSendRequest function is suspended until the response is received or an error occurs.
- tpf_httpSendAsyncRequest
- Sends an asynchronous HTTP request to a remote server and returns control to the ECB that called the tpf_httpSendAsyncRequest function after the request is sent. A z/TPF application is entered in a new ECB when the response is received or an error occurs.
- tpf_srvcInvoke
- Makes a synchronous service call to another application.
- tpf_srvcInvoke_ext
- Makes a synchronous or asynchronous service call to another application with extended options.
The high-speed connector selects a defined and available endpoint from the endpoint group that a message is sent to. The high-speed connector maintains a set of persistent socket connections to each selected endpoint and automatically load balances requests across the selected endpoints and the socket connections associated with them. In this way, the process of sending a user defined message or an HTTP request is simplified because the only action that a z/TPF application needs to take is to call a single function.
You can use the ZCONN command to manage an individual endpoint or an endpoint group. With this command, you can quiesce and stop endpoints to prevent the high-speed connector from using them. This action is useful when maintenance is applied to endpoints. Then, you can start the endpoints again and the high-speed connector automatically begins to use the endpoints again. You also can use the ZCONN command to display various statistical information for an endpoint or an endpoint group.
The endpoint group is defined through the endpoint group descriptor. The endpoint group descriptor is loaded to the z/TPF system through the version control file system and common deployment. Therefore, you can easily change the configuration while the system is running, without affecting existing ECBs in the system.
Figure 1 shows an example of using the high-speed connector in a customer application. The high-speed connector is used on the z/TPF system between an application and a server that supports TCP/IP. The high-speed connector simplifies the process of exchanging messages between the z/TPF application and the server and helps the system to access the Java application in a more efficient way.
