1.1 General: This standard series, IEC 61162-400 and upwards, specifies a communication protocol for use in integrated ship control (ISC) systems. IEC 61162-400 defines the overall functional scope for the communication systems. 1.2 Application profile: This part of IEC 61162 describes the application profile (A-profile - corresponding to ISO-OSI layers 5 to 7 [ISO 7498]) of the communication protocol which is the basis for the communication system. It relies on the realization of layers 1 to 4 (the T-profile) as described in part 401. The description of the A-profile is in the terms of services offered to the application using the protocol and of message contents and sequences used to realize these services.