MCNet (Mobile Communication Network)

MCNet builds upon the proven Controller Area Network (CAN). It was developed by Bosch for serial communications between electronic motor vehicle components. MCNet provides all necessary services for data transfer, including transport protocol and network management. The application messages needed to operate typical components, such as audio, video and navigation devices, can easily be integrated in MCNet by means of a database interface.

Vector Informatik has in-depth experience in electronic networking using CAN. In cooperation with Bosch, we are offering a special MCNet-module for CANoe. In the scope of this joint venture Vector will also be offering consultation services and training seminars.

Specification:

You can get the MCNet specification from Bosch or from Vector. To get the specification from Vector, please open our request form (PDF), print it , fill it in, and send it by mail (not via fax) to

Vector Informatik GmbH
c/o Frau Monika Heller
Ingersheimer Str. 24
70499 Stuttgart
Germany

You will then get the specification as soon as possible. If MCNet is used without modifications, no licensing fees are incurred for the use of Bosch patents that are relevant to MCNet.

MCNet Conception:

New technologies and services such as Digital Audio Broadcasting (DAB) place high requirements on a system used for information and entertainment in motor vehicles. In spite of increasingly higher integration, stand-alone solutions will more and more merge into complex, networked systems. The Mobile Communication Division (K7) of Robert Bosch GmbH has developed the 'Mobile Communication Network, or in short, the MCNet standard for the communication of decentral components like tuner, CD changer, navigation, Telephone, Traffic Message Channel (TMC), DAB or traffic telematics terminals. The MCNet transmission protocol is based on the 'Controller Area Network' (CAN version 2.0 A) and used for the transmission of control and monitoring data as well as for data display in text format. Separate connecting lines are used for audio and video data, thus making it possible to set up very flexible networks of a very high technical level.

The data transmission is event-oriented. The average load on the bus system and thus also on the device processors decreases. This makes it possible to transmit longer tables or texts with no delays to be perceived by the user. In contrast to cyclical transmission with high redundancy, it is important for event-oriented transmission that no data get lost. This is achieved with the help of special safety mechanisms in the transmission protocol. The Mobile Communication Network supports connection-oriented communication, i.e. messages can be transmitted to or received from a particular address.

The MCNet specification follows the ISO layer model (International Organization for Standardization). The so-called OSI model (Open System Interconnection) allows for a clean separation between application and communication with defined interfaces. In addition to network management generelly used for setting up, monitoring and terminating of logical connections, MCNet includes the following communication layers:

• physical layer
• data link layer
• transfer layer
• adaptation layer

The physical layer (bus link, i.e. transmission / reception of a bit stream) and the data link layer (transmission / reception of CAN telegrams) are mainly covered by hardware. All of the other layers are implemented by software. The transfer layer splits up messages (segmentation) thus making it possible to transfer data of any length (i.e. no restriction through the CAN telegram with its maximum of 8 possible data bytes). This in turn means that, for example, software downloads can be carried out using MCNet. The transmission of higher data quantities can be interrupted for important messages at any time (expedited service). The adaptation layer represents the interface to the application.

The Mobile Communication Network and the underlying networking philosophy are tailored to the typical requirements of communication and information systems in vehicles and are therefore perfectly suited for 'Mobile Multimedia Applications'. The first MCNet components for the aftermarket entered into volume production in mid-1996. The MCNet transmission protocol or parts thereof are used in the OEM segment as well.

CANoe MCNet:

Essential for the development, test and maintenance of distributed systems is the provision of suitable tools. CANoe offers as an development environment for CAN projects the possibility to include user specific functions (e.g. on CAN based higher protocol layers) via a DLL interface.

For MCNet Vector offers a special DLL interface for CANoe. With this interface MCNet components can be simulated and data communication between the MCNet components in a real system can be observed.

For simulation the nodes will be equipped in the simulation setup of CANoe with the MCNet transport layer. Tasks, for example sending an application data block, can be realized through calling only one function.

For analyzing there is a special MCNet observer, which evaluates with the help of a MCNet database the CAN data traffic and shows the transmitted MCNet messages online.

The analyze and test functions of CANoe (e.g. use of panels, recording and offline evaluation of bus traffic, statistic analyze of bus traffic, ...) are of course also available for examination of MC-Networks.