What is an AUTOSAR : Architecture & Its Applications

In automotive systems, the electronic or electrical complexity is increasing. In a modern vehicle, they have above 100 engine control units which are known as ECUs. Each ECU includes a number of functions which must be rephrased frequently from the scratch once the hardware like the processor is changed. It is very important for automobiles to make application software independent with the help of its hardware. To achieve this, fundamental functions are executed in AUTOSAR to create and set up an open software architecture intended for automotive engine control units. This article discusses an overview of an AUTOSAR.

Introduction to Autosar

The AUTOSAR was developed by different automobile manufacturing companies in the year 2003 like BMW, Continental AG, Daimler-Benz, Robert Bosch GmbH, Siemens VDO, for establishing an open industry-standard architecture for electrical and electronic devices in an automobile. In the same year of November, the famous motor company like Ford was joined like a Core Partner. In the month of December, Toyota Motor Corporation & Groupe PSA was joined. In February 2008, after Siemens VDO Company was obtained through Continental, then it is ceased being an autonomous Core Partner for AUTOSAR.

In the year 2003, AUTOSAR has released four major software architectures for automotive industries. The AUTOSAR work can be divided into 3-phases. In the phase-1 from 2004 to 06, the basic development was done, in the phase-2 from 2007 to 09; the basic development was extended in architecture as well as methodology. In phase-3 from 2010 to 13, the protection and preferred improvements can be done. The adaptive platform work has begun in the year 2016 and the main development actions were published finally in a combined release of Classic, Adaptive & Foundation of AUTOSAR.

What is AUTOSAR?

The term AUTOSAR stands for “Automotive Open System Architecture”. It is standardized as well as open automotive software architecture. This architecture supports the interfaces within application software & basic functions of the vehicle. And also helps in establishing familiar software architecture of the engine control system for all the AUTOSAR associates.

AUTOSAR is used for providing intrinsic advantages to the associates to handle more complex electrical and electronic systems in a vehicle like simple integration, switch the functions within complex engine control (ECU) network & to control over the lifecycle of the whole product.

This automotive software architecture was developed jointly through different automobile manufacturers, tool developers, and suppliers. This platform will enhance the functionalities of a vehicle in the automotive industry without troubling the existing model.


The engine control unit of automotive includes the following features

  • A strong interface with the hardware like actuators and sensors
  • Interface with bus systems within the vehicle
  • Include 16/32 Bits microcontroller
  • Internal or External Flash Memory
  • Real-Time System

Autosar Architecture with Example

AUTOSAR layer architecture subdivides the software into five layers. At first, we observe an OSI based however characteristic layer model explains the hierarchical arrangement of AUTOSAR software. For this reason, it sub-divides into three parts like fundamental software, runtime environment & application layer. In every layer, certain software modules are abstracted & these layers communicate through interfaces.

AUTOSAR Architecture
AUTOSAR Architecture

The different layers of AUTOSAR architecture run on a microcontroller like an application layer, RTE (runtime environment), service layer, and BSW (basic software), etc. Each layer includes predefined software modules & services to make application software autonomous from the engine control unit.

Application Layer

The first layer of the AUTOSAR architecture is the application layer which supports implementing custom functionalities. It includes software components as well as several applications to execute exact tasks according to the instructions.

This layer includes three components like application software, ports of software & port interfaces. For these components, the architecture ensures standardized interfaces within the application layer. The software components of this layer will assist in generating easy applications to give support for the vehicle functions.

The interaction between these components can be permitted through exact ports with a virtual Function Bus. These ports will facilitate the interaction between BSW of AUTOSAR & software components.
This is an overview of the architecture of AUTOSAR and it supports real-time supplies and security constraints. Depending on the MCU, the standard platform supports different applications like security and networking by allowing engine control units of the vehicle to contact sensors & actuators of the vehicle.

RTE (Runtime Environment)

RTE is a middleware layer that provides communication services to the software components of AUTOSAR & applications includes AUTOSAR sensor or actuator parts. The main purpose of this is to make the software components independent for mapping to a precise engine control system.

The main features of RTE include the following.

  • It is specific for the engine control system & application.
  • It is generated for every engine control unit.
  • Its interface is totally independent of the engine control unit.

Service Layer

This is the main software layer that provides different functions like the following.

  • Operating system
  • Memory service
  • Network communication for vehicle
  • State management of engine control unit
  • Problem-solving service

This layer provides fundamental software modules & services for different applications.

The main features of the service layer include the following.

  • Specific for MCU (microcontroller unit) and an element of ECU hardware
  • The interface of this is independent for ECU as well as MCU

BSW (Basic Software)

The basic software layer includes three layers namely

  • ECU Abstraction Layer
  • Complex Drivers
  • MCAL (Microcontroller Abstraction Layer)

ECU Abstraction Layer

  • Interface with microcontroller abstraction layer and exterior device driver mainly provides right of entry to devices that are inside otherwise outside of the MCU.
  • The application programming interface is used to interface with MCU.
  • The main purpose of this layer is to create a higher software layer independent for engine control unit hardware layout.

The main features of the ECU abstraction layer include the following.

  • Mounting can be dependent on the hardware of ECU whereas independent on MCU
  • High order interface can be independent for MCU & ECU hardware units

Complex Drivers

These layers are used for multifaceted functions that are not available on other layers. This layer can directly access the MCU. The main examples are electrical values control, injection control, detection of position increase, etc.

The main purpose is to fulfill particular functions & timing necessities desired to operate compound sensors as well as actuators.

The main features of complex drivers include the following.

  • Mounting is extremely dependent on ECU, MCU, etc.
  • High order interface can be mounted and standardized based on the interface of AUTOSAR

MCAL (Microcontroller Abstraction Layer)

This software module is accessed directly on-chip MCU peripherals & exterior devices that are mapped with memory. The main purpose is to create a higher software layer independent for MCU.

The main features of MCAL include the following.

  • Mounting depends on MCU
  • The high order interface is not dependent on MCU.

Objectives of AUTOSAR

The main objectives of AUTOSAR include the following.

  • Activation of redundancy
  • The functions from one ECU to other ECU can be done within the network
  • Maintainability during the entire product life cycle
  • Incorporation of functional modules from many suppliers
  • Increased utilize of COTS hardware.
  • Software updates over the life span of the automobile.
  • Scalability to various automobiles
  • Implementation of essential functions like an industry-wide typical core solution
  • Safety requirements

Advantages and Disadvantages of AUTOSAR

The advantages of AUTOSAR include the following.

  • Software sharing can be possible between different companies
  • Reusability of software component
  • The basic software architecture is layered.
  • Consistency of interfaces
  • Interoperability
  • Software code can be reused.
  • Design flexibility is more
  • Cost and development time will be reduced
  • Efficiency can be increased within functional development
  • Transparency & distinct interfaces will allow new business models.

The disadvantages of AUTOSAR include the following.

  • Complexity
  • Initial Investment
  • Learning Curve

Applications of AUTOSAR

The applications of Autosar architecture include the following.

  • Infotainment
  • Sensors like LIDAR and RADAR
  • Predictive Maintenance
  • Electrification
  • ADAS Functions with a Camera
  • v2x
  • Map Updates
  • Automotive Apps


1). What is AUTOSAR?

The automotive open system architecture is one kind of automotive software architecture, which is developed by different automobile suppliers, manufacturers, etc.

2). What is the purpose of AUTOSAR?

This enables the use of a software design based on a component model for a vehicular system.

3). Is AUTOSAR an operating system?

No, but it has a specification for the operating system.

4). What is the role of RTE in AUTOSAR?

It is used to provide the infrastructure services for allowing communication to happen among the software components which access fundamental software modules like the operating system & communication service.

5). What are the layers in AUTOSAR architecture?

There are three types of layers like RTE, service layer, and basic software.

6). Who developed this AUTOSAR architecture?

It is developed by tool developers, automobile suppliers, and its manufacturers.

7). How to learn AUTOSAR?

First, learn the basics from experienced persons and start doing projects to develop the ECUs depending on its architecture. In addition, make some samples within Matlab & go through the generated code.

Thus, this is all about an overview of AUTOSAR. It is a standardized automobile software architecture, which is developed by various automobile suppliers, manufacturers. The main objective of this is to set up a layer among application software & the ECU hardware. Therefore, this software is mainly independent of any preferred microcontrollers as well as a car manufacturer to make it reusable for a number of individual engine control unit systems. Here is a question for you, what is the full form of AUTOSAR?