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In-vehicle networks (IVN) have been standardized from the beginning. The story of IVN standardization started at the beginning of the 90s. Today, several IVN technologies have been internationally standardized by ISO (International Organization for Standardization) including the related conformance test plans. But as all electronic technologies, IVNs are a matter of improvement and change due to new requirements and gained experiences. This makes it difficult to always keep the standard backwards compatible, in particular if immature approaches are submitted. Furthermore, new communication protocols are knocking on the door of international standardization bodies. The automotive industry itself is conservative and adapts new IVNs slowly. There are also concerns regarding too many different bus systems and networks in one vehicle. This paper discusses the benefits and challenges of the standardization of IVNs.

The CAN FD protocol internationally standardized in ISO 11898-1:2015 just describes how to implement it into silicon. The ISO 11898-2:2016 standard specifies the physical media attachment (PMA) sub-layer of the CAN (FD) physical layer. The design of CAN FD networks is not in the scope of these standards. In general, the physical layer design of CAN FD networks requires more attention compared with Classical CAN networks. First recommendations have been developed. Different standardization bodies have already specified or are in the process of specifying higher-layer protocols, for example ISO for on-board diagnostic, ASAM for calibration, etc.

Police cars, taxi/cabs, and other special-purpose passenger cars are equipped with add-on devices such as blue-light, special horns, taximeter, digital radio, etc. In the past, such equipment was connected via discrete I/O lines or proprietary interfaces, e.g. RS-232, RS-485, J1850, or CAN. The CAN in Automation (CiA) international users and manufacturers group has established a technical group specifying an open CAN-based network for such car add-on devices. The physical layer is based on ISO 11898-2 (CAN high-speed), and the CAN data link layer (ISO 11898-1) uses the base frame format (11-bit CAN identifier). The selected application layer is compliant to CANopen (EN 50325-4). In order to achieve easy system integration, the group is specifying an application profile describing the content of the transmitted messages.

The TTCAN (time-triggered communication on CAN) protocol is based on CAN (Controller Area Network). It may use standardized CAN physical layers such as specified in ISO 11898-2 (high-speed transceiver) or in ISO 11898-3 (fault-tolerant low-speed transceiver). TTCAN provides mechanism to scheduled CAN messages time-triggered as well as event-triggered. This will allow using CAN-based networks to close control loops. Another benefit is the increase of real-time performance in CAN-based in-vehicle networks.

J1939-based networks are used in most of the in-vehicle networks in trucks and buses and in some off-highway vehicles. In Europe, many of the super-construction manufacturers like to use off-the-shelf, price-competitive CANopen devices originally developed for other applications fields. CANopen is a standardized CAN-based application layer and profile specification. In order to standardize the gateway functionality, a CANopen standardized truck gateway profile is introduced.

J1939-based networks are used in most of the in-vehicle networks in trucks and buses and in some off-road vehicles. In addition, some off-highway vehicles such as agriculture and forestry machines and military vehicles are equipped with J1939-based networks. Because in Europe, many of the super-construction manufacturers like to use off-the-shelf, price-competitive devices originally developed for other applications fields, they like to buy CANopen-based modules. CANopen is a standardized CAN-based application layer and profile specification. In order to standardize the gateway functionality, a CANopen device profile for J1939 truck gateway is introduced.

The reviewed ISO 11898 standard has been completely restructured. It is now divided in two parts: ISO 11898-1 specifies the data link layer with its LLC and MAC sub-layers; ISO 11898-2 describes the high-speed MAU and MDI sub-layers. The reviewed documents has been harmonized with the C and VHDL models from Bosch, this is mainly the integration of the implementation guidelines. In addition, an optional Bus Monitoring Mode and the Time-Triggered Communication (TTC) option have been specified.

CANopen is a CAN-based higher layer protocol originally developed for industrial control systems. The CANopen specifications include different device and application profiles. CANopen networks are also used in vehicles, e.g. in buses for engine control, in public transportation for passenger information systems, and in off-road vehicles for different purposes. As opposed to other higher-layer approaches, CANopen software is first compiled and afterwards the network will be configured. In traditional vehicle networks configuration is done before compilation. Besides the use in a hybrid bus, CANopen is already implemented in different fork-lifts, road construction machines, as well as mining vehicles. CiA is developing device profiles for diesel engines, electronic gears, joysticks, hydraulic valves, etc. In addition, CANopen has been used in agriculture and forrestry machines and maritime applications.

CANopen is a CAN-based higher layer protocol originally developed for industrial control systems. The CANopen specifications include different device and application profiles. CANopen networks are also used in vehicles, e.g. in buses for engine control, in public transportation for passenger information systems, and in off-road vehicles for different purposes. In opposite to other higher-layer approaches, CANopen software is first compiled and afterwards the network will be configured. In traditional vehicle networks configuration is done before compilation.

Several companies have implemented in silicon the international standardized Controller Area Network (ISO 11898). The layered data link layer provides basic communication services such as transmission of data and requesting of data. The CAN protocol also handles the detection of failures as well as the error indication. All existing implementations use the same protocol handler, which has to be compliant with the C or VHDL reference model from Bosch. The implementations differ in the acceptance filtering, the frame storage capabilities, and in additional, nice-to-have features.