# Service mapping

Source: [https://docs.qualcomm.com/doc/80-41102-1/topic/service-mapping.html](https://docs.qualcomm.com/doc/80-41102-1/topic/service-mapping.html)

- An RPC service is one-to-one mapped to a SOME/IP service.
- The RPC services are declared via the JSON configuration file in
                        /legato/systems/current/appsWriteable/tafRpcProxy/taf\_rpc.json,
                    which shall be applied for all TelAF systems within the vehicle.
- The default SOME/IP base service ID is 0xED00. Each RPC service uses a global
                    offset starting from 1 to determine its SOME/IP service ID. If needed, the base
                    service ID can be changed in the JSON file.
- The default SOME/IP base port number is 40000. Each RPC service uses a global
                    offset starting from 1 to determine its port number. If needed, the base port
                    number can be changed in the JSON file.
- The SOME/IP service instance ID is mapped to its system ID so that the RPC proxy
                    can distinguish the same TelAF service on different systems.
- The RPC proxy creates a local TelAF proxy service for each RPC service on the
                    remote systems once the corresponding SOME/IP service is available.

**Parent Topic:** [TelAF RPC](https://docs.qualcomm.com/doc/80-41102-1/topic/rpc.html)

Last Published: Aug 06, 2026

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