Note: There is a newer version of this specification see VEC 2.0.2
A NetSpecification is the most abstract way to describe a vehicle electrical system. It is a container for various NetworkNodes, Nets and NetGroups. A NetSpecification is used if the physical links between electrical components are specified without specifying a concrete network topology and a physical realization. In many processes and applications this is defined as "Architectural Layer".
A NetworkNode is a representative for an actor in the electric system, e.g. an actuator, a sensor, an ECU. It can define various NetworkPorts, which can be classified as a signal source (in the case that the attribute signalDirection has got the value Out) or as a signal sink (in the case that the attribute signalDirection has got the value In) or with changing behaviour (in the case that the attribute signalDirection has got the value InOut).
Note: According to the definition above inliners (normally) and splices are no NetworkNodes and so are not represented within a NetSpecification. In some cases, there are architectural relevant inliners (NetworkNodeType = CouplingDevice) that represented in the architectural layer.
A Net is a representative of an abstract link between the referenced NetworkPorts and can be related to a NetType.
Note: A Net itself doesn’t define:
- How the topology of the conducting connection must be realized (e.g. if three NetworkPorts are interconnected, the Net makes no definition if this physical three-point connection is realized with a splice, an insulation displacement connector or a double contact.).
- How the physical connections must be realized (e.g. if a certain BUS Connection is realized by a pair of wires or four wires).
Note: Normally, a Net references at least two NetworkPorts. However, in the very early stages of product development it might be the case that some NetworkNodes with NetworkPorts which are source of a dedicated Net are already defined – but the counterparts are not. This is an example where it can be useful to define Nets referencing only one NetworkPort.