What is ISO 20794‑3 about?
ISO 20794‑3 is part three of the multi-series standard that specifies the OSI transport layer and network layer by means of services and protocols.
They can be used by different applications.
The transport layer:
- Transforms a message into a single packet
- Adds protocol control information for diagnostic and node configuration into each packet
- Adds packet identifier for diagnostic and node configuration into each packet; and
- Performs transport protocol error detection
The network layer:
- Adds a node address for diagnostic and node configuration into each segment
- Observes timing for diagnostic and node configuration of each segment
Note-
The transport layer protocol is not used for normal communication except to map the service interface parameters between lower and upper OSI layers.
The network layer is not used for normal communication except to map the service interface parameters between lower and upper OSI layers.
Who is ISO 20794‑3 for?
ISO 20794‑3 on transport and network layer is useful for:
- Road vehicle manufacturers
- Designers and developers of clock extension peripheral interface (CXPI)
- Automotive engineers
- Vehicle switches and sensors manufacturers
- Network layer designers and developers
Why should you use ISO 20794‑3?
CXPI is an automotive low-speed single-wire network. It is an enabler for reducing vehicle weight and fuel consumption by reducing wire counts to simple devices like switches and sensors.
CXPI serves as and is designed for automotive control applications, for example, door control group, light switch, and HVAC (Heating Ventilation and Air Conditioning) systems.
ISO 20794‑3 describes the transport layer and network layer for the clock extension peripheral interface (CXPI). The transport layer and network layer helps to
- Transforms a message into a single packet
- Adds protocol control information for diagnostic and node configuration into each packet
- Adds packet identifier for diagnostic and node configuration into each packet
- Performs error detection and reports the result to higher OSI layers
ISO 20794‑3 specifies the service interface parameters and data types, which are used by the transport and network layer services.