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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.

Industrial vehicles cover a broad range of different applications including fork-lifts, agriculture and forestry machines, as well as road construction machines and truck-based cranes, garbage trucks and even truck-based aircraft washing robots. All of these vehicle applications are characterized by low-volume to mid-volume production. There is also a high variety in different versions. That is the reason why in these applications embedded networks should be standardized. In addition, the vehicle manufacturers like to use off-the-shelf products, even if they are manufactured for other market fields, in order to get better prices.

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.

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.