The Memory Access Service is used to asynchronously read and write to memory-based devices across a network. The Memory Access Service is based on the CCSDS SOIS Memory Access Service and provides a layer of abstraction between applications and memory-based devices. It provides a common API for applications to use regardless of the data link and protocols. Applications use abstract identifiers when referencing memory devices and the Memory Access Service translates the identifiers to the specific access method, such as using the Remote Memory Access Protocol (RMAP) over SpaceWire.
In order to have a Memory Access Service, JAS requires that the data link supports a protocol to access memory-based devices across a network. If a protocol doesn’t exist for a data link, the RMAP protocol can be used as a starting point for a specification. This may require that certain hardware and software infrastructure be developed. Regardless of the protocol, the intent is that the Memory Access Service provides a seamless interface for applications to access hardware remotely across a network.