DDS15 — Deprecate Basic Service Mapping

The Basic Service Mapping was included in the specification primarily to support implementations that did not support XTYPES. Now that most DDS support XTYPES this motivation is no longer there.

Having both a Basic Service Mapping and an Enhance Service Mapping creates significant complexity and ambiguity. It becomes another choice the user must make and another way implementations may not interoperate.

Furthermore when other specifications map to DDS Services, they must too make a choice of Service Mappings. Hence perpetuating complexity and interoperability issues.

The Enhanced Service Mapping has significant advantages in terms of performance, scalability, and type-system simplicity. Fundamentally it allows the use of the same types for request reply and RPC, any extra information is added in meta-data so that the types themselves are unpolluted. This is in-line with what other middleware technologies (e.g. JMS) does.

Therefore the most sensible thing is to deprecate the Basic Service Mapping.