BS ISO 15765-1:2011 pdf download.Road vehicles— Diagnostic communication over Controller Area Network (DoCAN) Part 1: General information and use case definition.
5.2 Open Systems Interconnection (OSI) model
ISO 15765 is based on the Open Systems Interconnection (OSI) Basic Reference Model as specified in ISO/IEC 7498-1 which structes communication systems into seven layers.
All parts of ISO 15765 are guided by the OSI service conventions as specified in ISO/IEC 10731 to the extent that they are applicable to diagnostic services. These conventions define the interaction between the service user and the service provider through service primitives.
The aim of this subclause is to give an overview of the OSI model and show how it has been used as a guideline for this part of ISO 15765, It also shows how the OSI service conventions have been applied to ISO 15765.
The OSI model structures data communication into seven layers called, from top down, application layer
(layer 7), presentation layer (layer 6), session layer (layer 5), transport protocol layer (layer 4). network layer
(layer 3), data link layer (layer 2) and physical layer (layer 1).
A subset of these layers is used in ISO 15765. which specifies the application, session, transport protocol. network, data link and physcaI layers for D0CAN.
The purpose of each layer is to provide services to the layer above. The application layer provides services to the diagnostic application. The active parts of each layer, implemented in software, hardware or any combieation of software and hardware, are called entities. In the OSI model, communication lakes place between entities of the same layer in different nodes. Such communicating entitles of the same layer are called peer entitles.
The services provided by one layer are available at the Service Access Point (SAP) of that layer. The layer above can use them by exchanging data parameters.
ISO 15765 dIstinguishes between the services provided by a layer to the layer above It and the pro(000l used by the layer to send a message between the peer entities of that Layer. The reason for this distinction is to make the services, especially the application layer services arid the transport layer services, reusable for CAN and for other network types. In this way, the protocol is hidden from the service user and it is possible to change the protocol if special system requirements demand it.
ISO 15765 is based on the Open Systems Interconnection (OSI) Basic Reference Model as specified in ISO/IEC 7498-1 which structes communication systems into seven layers.
All parts of ISO 15765 are guided by the OSI service conventions as specified in ISO/IEC 10731 to the extent that they are applicable to diagnostic services. These conventions define the interaction between the service user and the service provider through service primitives.
The aim of this subclause is to give an overview of the OSI model and show how it has been used as a guideline for this part of ISO 15765, It also shows how the OSI service conventions have been applied to ISO 15765.
The OSI model structures data communication into seven layers called, from top down, application layer
(layer 7), presentation layer (layer 6), session layer (layer 5), transport protocol layer (layer 4). network layer
(layer 3), data link layer (layer 2) and physical layer (layer 1).
A subset of these layers is used in ISO 15765. which specifies the application, session, transport protocol. network, data link and physcaI layers for D0CAN.
The purpose of each layer is to provide services to the layer above. The application layer provides services to the diagnostic application. The active parts of each layer, implemented in software, hardware or any combieation of software and hardware, are called entities. In the OSI model, communication lakes place between entities of the same layer in different nodes. Such communicating entitles of the same layer are called peer entitles.
The services provided by one layer are available at the Service Access Point (SAP) of that layer. The layer above can use them by exchanging data parameters.
ISO 15765 dIstinguishes between the services provided by a layer to the layer above It and the pro(000l used by the layer to send a message between the peer entities of that Layer. The reason for this distinction is to make the services, especially the application layer services arid the transport layer services, reusable for CAN and for other network types. In this way, the protocol is hidden from the service user and it is possible to change the protocol if special system requirements demand it.
