2.3.5 Multiple Applications and Multiple Service Providers

An understanding of the relationship between Service Providers, applications, and other Service Providers depends on the environment in which Service Providers are embedded. This can be shown as follows:

The TSPI environment is shown. Multiple different Service Providers coexist at the same time. Multiple different Applications coexist at the same time. A single Application can use several different Service Providers at once as shown by the solid arrows. Similarly, several different Applications can use the same Service Provider at once as shown by the dashed arrows. The TAPI DLL takes care of merging and splitting the streams of commands and events being exchanged between Applications and Service Providers.