AUTOSAR

AUTomotive Open System ARchitecture (AUTOSAR) is a global development partnership of automotive interested parties founded in 2003. It pursues the objective to create and establish an open and standardized software architecture for automotive electronic control units (ECUs). Goals include the scalability to different vehicle and platform variants, transferability of software, the consideration of availability and safety requirements, a collaboration between various partners, sustainable use of natural resources, and maintainability during the whole "product lifecycle".
History.
The AUTOSAR development partnership was formed in July 2003 by Bavarian Motor Works (BMW), Robert Bosch GmbH, Continental AG, Daimler AG (formerly Daimler-Benz, then DaimlerChrysler), Siemens VDO, and Volkswagen to develop and establish an open industry standard for automotive electrical-electronic (E/E) architecture. In November 2003, Ford Motor Company joined as a Core Partner, and in December, Groupe PSA (formerly PSA Peugeot Citroën) and Toyota Motor Corporation joined. The following November, General Motors also became a Core Partner. After Siemens VDO was acquired by Continental in February 2008, it ceased being an independent Core Partner of AUTOSAR.
Since 2003, AUTOSAR has provided four major releases of the standardized automotive software architecture for its Classic Platform and one release of Acceptance Tests. The work of AUTOSAR can be divided into three phases:
In 2013, the AUTOSAR consortium entered a continuous working mode for its Classic Platform to maintain the standard and provide selected improvements, including releases R4.2, and 1.0 of Acceptance Tests.
In 2016, work on the Adaptive Platform began. A first release (17-03) was published in early 2017, followed by release 17-10 in October 2017 and release 18-03 in March 2018. With release 18-10 in October 2018, the major development activities were finally published in a joint release of AUTOSAR Classic, Adaptive, and Foundation.
In December 2020, AUTOSAR R20-11 was virtually released.
Concept and goals.
AUTOSAR provides a set of specifications that describes basic software modules, defines application interfaces and builds a common development methodology based on standardized exchange format. Basic software modules made available by the AUTOSAR layered software architecture can be used in vehicles of different manufacturers and electronic components of different suppliers, thereby reducing expenditures for research and development and mastering the growing complexity of automotive electronic and software architectures. 
Based on this guiding principle, AUTOSAR has been devised to pave the way for innovative electronic systems that further improve performance, safety, and environmental friendliness and to facilitate the exchange and update of software and hardware over the service life of the vehicle. It aims to be prepared for the upcoming technologies and to improve cost-efficiency without compromising quality.
Software architecture.
AUTOSAR uses a three-layer architecture:
Classic Platform.
The AUTOSAR Classic Platform is the standard for embedded real-time ECUs based on OSEK. Its main deliverable is specifications. 
The AUTOSAR Classic Platform architecture distinguishes on the highest abstraction level between three software layers that run on a microcontroller: application, runtime environment (RTE) and basic software (BSW). The application software layer is mostly hardware independent. Communication between software components and access to BSW happens via RTE, which represents the full interface for applications. 
The BSW is divided in three major layers and complex drivers: 
Services are divided further, into functional groups representing the infrastructure for system, memory and communication services.
One essential concept of the Classic Platform is the Virtual Functional Bus (VFB). This virtual bus is an abstract set of RTEs that are not yet deployed to specific ECUs and decouples the applications from the infrastructure. It communicates via dedicated ports, which means that the communication interfaces of the application software must be mapped to these ports. The VFB handles communication within the individual ECU and between ECUs. From an application point of view, no detailed knowledge of lower-level technologies or dependencies is required. This supports hardware-independent development and usage of application software.
The Classic Platform also enables the integration of non-AUTOSAR systems such as GENIVI by using the Franca Interface Definition Language (Franca IDL).
Adaptive Platform.
New use-cases required the development of the Adaptive Platform. One prominent example is highly automated driving, in the context of which the driver temporarily and/or partially transfers responsibility for driving to the vehicle. This can require communication with traffic infrastructure (e.g. traffic signs and -lights), cloud servers (e.g. to access the latest traffic information or map data), or the use of microprocessors and high-performance computing hardware for parallel processing, e.g., graphics processing units (GPUs).
Further, Car-2-X applications require interaction to vehicles and off-board systems. That means that the system has to provide secure on-board communication, support of cross-domain computing platforms, smartphone integration, integration of non-AUTOSAR systems, and so on. Also, cloud-based services will require dedicated means for security, such as secure cloud interaction and emergency vehicle preemption. They will enable remote and distributed services, such as remote diagnostics, over the air (OTA) update, repair, and exchange handling.
To support dynamic deployment of customer applications and to provide an environment for applications that require high-end computing power AUTOSAR is currently standardizing the AUTOSAR Adaptive Platform. Its core is an operating system based on the POSIX standard. The operating system can be used from the application via a subset of the POSIX according to IEEE1003.13 (namely PSE51). One of the key features of the Adaptive Platform is service-oriented communication since the Platform is based on the Service - Oriented Architecture.
The Adaptive AUTOSAR is developed and written using C++ which is an Object Oriented Programming language. The communication protocol used for the in-vehicle networking using the Adaptive platform is SOME/IP based on the Ethernet Communication Protocol.
For the Adaptive Platform two types of interfaces are available: services and application programming interfaces (APIs). The platform consists of functional clusters which are grouped in services and the AUTOSAR Adaptive Platform foundation. 
Functional clusters:
Functional clusters in AUTOSAR Adaptive Platform have to have at least one instance per (virtual) machine while services may be distributed in the in-car network.
Adaptive Platform services include: 
The AUTOSAR Adaptive Platform contains both specification and code. In comparison to the Classic Platform, AUTOSAR develops an implementation to shorten the validation cycle and illustrate the underlying concepts. This implementation is available to all AUTOSAR partners. 
Foundation.
The purpose of the Foundation standard is to enforce interoperability between the AUTOSAR platforms. The foundation contains common requirements and technical specifications (for example protocols) shared between the AUTOSAR platforms, and the common methodology.
Acceptance Tests.
In 2014, AUTOSAR Acceptance Tests were introduced to minimize test efforts and costs. Acceptance Test Specifications are system test specifications using the specified interfaces of the respective Platform. Also, they are considering the specified behavior on the bus. They can be seen as a black box test case for a given platform function. The specification of standard acceptance tests contributes to these objectives.
Standardized Application Interfaces.
Standardization of functional interfaces across manufacturers and suppliers and standardization of the interfaces between the different software layers is seen as a basis for achieving the technical goals of AUTOSAR. Only by standardizing concrete interface contents in their physical and temporal representation allows achieving the needed integration compatibility.
Organization.
AUTOSAR defined six different levels of membership. The contribution of partners varies depending on the type of partnership:
Core Partners include the founding partners BMW, Bosch, Continental, Daimler AG, Ford, General Motors, PSA Peugeot Citroën, Toyota, and Volkswagen. These companies are responsible for organization, administration and control of the AUTOSAR development partnership. Within this core, the Executive Board defines the overall strategy and roadmap. The Steering Committee manages day-to-day non-technical operations and admission of partners, public relations and contractual issues. The Chairman and Deputy of Chairman, appointed for one year, represent the Steering Committee for that purpose. The AUTOSAR Spokesperson takes over the communication with the outside world.
Strategic Partners are appointed for a period of two years from the circle of Premium Partners and support the project leader team in the various technical, organizational and everyday processes. They also give new strategic inputs to the project leader round.
Premium and Development members contribute to work packages coordinated and monitored by the Project Leader Team established by the Core Partners. Associate partners are making use of the standard documents AUTOSAR has already released. Attendees are currently participating with Academic collaboration and non-commercial projects.
As of mid-2019, more than 270 companies participate in the AUTOSAR development partnership.
AUTOSAR vendors.
"Selection of vendors, which provide a full AUTOSAR solution, including RTOS, BSW, design tools, compiler, etc."
AUTOSAR-related software vendors and partners.
"Selection of vendors, which provide AUTOSAR-related tools and software, e.g. for testing, diagnostics, development, etc."