Distributed SOM (DSOM) and the Replication Framework require basic message services for inter-process communications. The Event Management Framework must be integrated with the same communication services in order to handle communications events.
To maximize their portability to a wide variety of local area network transport protocols, the DSOM, Replication, and Event Management Frameworks have been written to use a common communications interface, which is implemented by one or more SOM class libraries using available local protocols.
The common communications interface is based on the "sockets" interface used with TCP/IP, since its interface and semantics are fairly widespread and well understood. The IDL interface is named Sockets. There is no implementation associated with the Sockets interface by default; specific protocol implementations are supplied by subclass implementations.
Note: The Sockets classes supplied with the SOMobjects Developer Toolkit and run-time packages are only intended to support the DSOM, Replication, and Event Management Frameworks. These class implementations are not intended for general application usage.
Available Sockets subclasses by SOMobjects product are as follows:
Note: The TCPIPSocket32 class gives greater performance over the TCPIPSockets class on OS/2, but requires the 32-bit version of TCPP/IP (version 2.0) rather than the 16-bit version of TCP/IP (version 1.2.1).
Application developers may need to develop their own Sockets subclass if the desired transport protocol or product version is not one of those supported by the SOMobjects run-time packages. This appendix explains how to approach the implementation of a Sockets subclass, if necessary.
Warning: this may be a non-trivial exercise!