Cookies: Our site uses cookies in order to deliver better content. By continuing you accept these cookies.


(DoIP) Diagnostics Over Internet Protocol Explained

Updated at 20 Dec, 2022

— Unlock the future of online diagnostics with DoIP. Discover how it empowers you to access vehicle data remotely via the internet.

(DoIP) Diagnostics Over Internet Protocol Explained
In the ever-evolving world of automotive technology, the role of digital protocols cannot be overstated. Enter DoIP, or Diagnostics Over Internet Protocol, a game-changing development in the realm of vehicle diagnostics. By 2022, a significant portion of new vehicles had already incorporated DoIP, enabling seamless remote access to onboard diagnostics data. In this article, we'll dive deep into the nuances of DoIP, explaining why it's proclaimed as the future of online diagnostics.

As our world becomes increasingly interconnected with a growing number of devices linking up to the internet, the demand for advanced communication protocols, especially for remote diagnostics of complex systems like automobiles, had surged. At the heart of these advancements stands DoIP, a crucial protocol in this arena.

Outline of a sports car with DOIP nodes labeled, illustrating the concept of Diagnostics Over Internet Protocol.

What is DoIP? Getting to the Basics.

DoIP, short for "Diagnostics over Internet Protocol," is a revolutionary communication protocol primarily designed for remote diagnostics of vehicles, but it holds potential for much more. As the field of the Internet of Things (IOT) grows, and numerous devices, including telematics systems, connect online, the possibilities for remote diagnostics and repairs broaden considerably.

At its core, DoIP was designed to bridge the communication between external diagnostics tools and a vehicle's electronics control units (ECUs). Thanks to this protocol, you can now tap into the diagnostic data of a car's onboard computer system (OBD2), even if the vehicle is miles away on a distant road. This becomes incredibly handy for spotting issues with vital parts like the engine, gearbox, or brakes. Once identified, you can design repair strategies, order parts, and undertake fixes without every physically engaging with the vehicle.

But did you know that DoIP has its roots in the ISO 13400 standards and is a key transport mechanism for diagnostics data?

Such data, if left unprotected, could be an avenue for potential cyberattacks on vehicles. Recent studies and analyses reveal that while DoIP is groundbreaking, its current design doesn't inherently guarantee top-notch security. Notably, critical security features, like the Transport Layer Security (TLS) and client authentication, aren't mandatory in the DoIP protocol.

This poses vulnerabilities, but on the bright side, we've identified measures to counteract these weaknesses, ensuring a safer user experience. Keep on reading to find out how.

AutoPi TMU CM4
Stay Ahead of the Curve!

Embrace the future with remote vehicle diagnostics. Gain real-time insights and enhance vehicle performance.

How Does DoIP Ensure Secure Remote Vehicle Diagnostics?

Essentially, the DoIP gateway facilitates communication with all ECUs connected, eliminating the hassle and cost of embedding the DoIP protocol stack in each unit individually.

To initiate the diagnostic process, a diagnostic tester tool plays a vital role. It forwards diagnostic requests to the vehicle via Ethernet and, in return, acquires a diagnostic response. This streamlined process signifies the evolutionary leap from traditional cars to what is now commonly referred to as "computers on wheels."

However, a point of conflict arises when we discuss security. As mentioned, though DoIP has transformative capabilities, it's relevant to note that both Transport Layer Security (TLS) and client authentication aren't primarily obligatory within the DoIP protocol. This can raise eyebrows regarding data integrity and security.

Here at AutoPi, we're ahead of the curve. Whenever data is transferred, it's encrypted using HTTPS, ensuring data transmission remains uncompromised. Our prioritization of security guarantees that your vehicle's diagnostic data is not only accurate but also guarded against potential threats.

Outline of a sports car with DOIP nodes labeled, illustrating the concept of Diagnostics Over Internet Protocol.

DoIP Protocol for UDS: Unpacking ISO 13400-2 & 14229-5

Unified Diagnostics Services (UDS), as detailed by the ISO 14229 standard, is a cornerstone protocol empowering diagnostic systems to interface seamlessly with vehicle ECUs. It incorporates various diagnostics protocols such as KWP 2000 (ISO 14230) and diagnostics on CAN (ISO 15765). This ensures that UDS remains universally compatible and independent of specific vehicle brands. Today, UDS stands out as one of the dominant standards in the diagnostics realm.

The superiority of UDS is further elevated with the incorporation of the DoIP Transport Layer (ISO 13400-2). This innovative layer is designed with specialized features to foster and uphold connections between external testing equipment and the DoIP gateway inside vehicles.

ISO 13400, in its entirety, envisions a harmonized vehicle interface that provides a consistent communication interface irrespective of the in-vehicle network evolution. It draws inspiration from the Open System Interconnection (OSI) Basic Reference Model, structuring communication into seven crucial layers. Within this framework:

  • The UDS, found in ISO 14229-1, ISO 14229-2, and ISO 27145-3, situates itself in the seventh layer.

  • Presentation nuances, be it enhanced diagnostics or global onboard diagnostics, settle within the sixth layer.

  • ISO 14229-2 defines session layer services, placing them in the fifth layer.

  • ISO 13400-2, vital for our discussion, specifies both the transport protocol (fourth layer) and network layer (third layer) services.

  • Lastly, the physical and data link services find their residence in layers one and two as described in ISO 13400-3.

The architecture of UDS, comparable to the CANopen protocol, is rooted in the OSI model. Notably, the UDS software stack holds the unique capability of storing fault codes within the ECU memory, documenting every vehicle issue and subsequently relaying this data to the client. This strategic alignment guarantees that ethernet-based DoIP can comfortably support transfer rates climbing up to 100mbps - a marked improvement over the 500kbps in CAN systems.

To navigate the nuances of vehicle diagnostics, it's essential to harness the cohesive power of the DoIP and UDS, anchored firmly by the ISO 13400-2 & 14229-5 standards. It's not just about understanding vehicles, but about pioneering their connectivity and diagnostic potential for the future.

Insights on UDS protocol, Ethernet limitations, and ECU data storage.

DoIP's Enhanced Performance on Ethernet Networks

Automotive ethernet, a cornerstone for establishing local area networks (LANs) in vehicles, has long facilitated interconnected devices within confined automotive environments. Originating from the 1990s, its core advantage lies in allowing multiple onboard devices to transmit data seamlessly.

It's crucial to distinguish between Ethernet and the Internet. While the latter serves as a communication backbone for global connectivity, Ethernet is purely a LAN-focused protocol, enabling devices within a limited proximity to communicate. In this case, enabling devices within vehicles to communicate.

The diagnostics capabilities of automotive ethernet have seen expansive use, especially in the realm of flashing ECUs. Such applications have become indispensable for vehicle manufacturers and suppliers, as they drastically shorten flash cycles, both in production lines and car repair facilities.

The IP in DoIP stands for "Internet Protocol." An IP address is a unique identifier assigned to every device in a network, allowing it to communicate within the vast expanse of the internet.

As defined by ISO 13400, Diagnostics over IP (DoIP) brings this diagnostic capability to the forefront. Its versatility is evident, as it doesn't rely strictly on a specific physical layer but only requires the transmission of IP packets. Thus, apart from automotive ethernet, DoIP's functionality can extend to other mediums like WLAN and UMTS, broadening its applicative spectrum.

Illustration of LAN setup with Ethernet connection between computers and explanation of its function separate from the Internet.

Key differences between UDS on IP and UDS on CAN

Diving into the world of vehicle diagnostics, we compare the nuances of UDS on IP with the traditional UDS on CAN. Here's a concise breakdown of their layers and unique advantages.

Graphic detailing UDS on IP benefits like improved latency and error reduction in data transmission.


  • Uses UDS application layer (ISO 14229-5): The framework for diagnostics over internet protocols.

  • Implements DoIP transport layer (ISO 13400-2): Enables seamless vehicle-to-network communication.

  • Operates on Ethernet physical layer (IEEE 802.3): A robust foundation for data transfer.


  • Utilizes UDS application layer (14229-3): Tailored for Controller Area Networks.

  • Deploys CAN transport layer (ISO 15765-2): Facilitates data exchanges on CAN setups.

  • Relies on CAN physical layer (ISO 11898): The backbone of CAN network communication.

Key Distinctions:

  • ISO 14229-5 standard: A guideline for UDS on IP setups.

  • ISO 14229-3 standard: Dictates UDS on CAN functionalities.

  • UDS on IP surpasses CAN bus efficiency in:

    • Faster data transmission: Speed is paramount.

    • Handling larger data volumes: More data, fewer hassles.

    • Data format reducing errors: Precision-driven diagnostics.

Benefits of Ethernet MAC Layer in DoIP Stack:

  • Uses lightweight, simple shielded cables: Enhanced durability, minimized interference.

  • Economical, high bandwidth technology: Quality at an affordable rate.

  • Offers a flexible communication platform: Adaptability is the key.

  • With ISO 14229-5 application layer, UDS integrates with IP: Seamless synchronization.

  • DoIP connections: Set manually or auto-established when the vehicle is online. Ensuring constant connectivity.

Stay Updated with Your ECU!

Unlock real-time insights and optimize your driving with AutoPi TMU. Be in tune with your ECU.

Features of ISO 13400-2:2012 for Modern Vehicle Diagnostics

ISO 13400-2:2012 sets out requirements for both vehicle gateways and testing equipment. Crucial for diagnostic communication, its key features include:

  • Vehicle announcement and discovery.

  • Integration into vehicle networks.

  • Managing errors.

  • Retrieving basic vehicle status.

  • Establishing connections.

  • Data routing.

Additionally, ISO 13400-2:2012 offers optimal functionalities like:

  • Firewall capabilities within DoIP entities.

  • Monitoring the status of DoIP entities.

As vehicles evolve to offer enhanced connectivity and sophisticated telematics services, the use of DoIP is on the rise. It's closely tied to automakers' journey towards creating smarter vehicles and holds potential significance for IoT platforms. Given the constraints of embedded systems, the integration of a streamlined TCP/IP is vital.

Maximizing DoIP Benefits with AutoPi

The AutoPi TMU CM4 allows for upgrades to support DoIP. In combination with the AutoPi Cloud, it offers a DoIP/UDS add-on that can be seamlessly integrated. Notably, the system is configurable and customized to suit your needs, regardless of your fleet size.

Try our platform for FREE here!

The AutoPi System

Drive into the Future

Leverage DoIP for next-gen fleet diagnostics.

Other posts you will like

Ideal Car Solutions: Customize Your Projects
Guides Internet of Things

Ideal Car Solutions: Customize Your Projects

Ideal car solutions for 2021 are modern upgrades of vehicles, such as Asset Tracking, Keyless Entry, Voice Recognition and more.

CANopen Guide (2024): Simplified Intro to Network Protocols

CANopen Guide (2024): Simplified Intro to Network Protocols

Explore CANopen with our easy guide, perfect for beginners. Get a simplified introduction to the key essentials of CAN-based network protocols in auto ...

The Ultimate (2024) Guide to J2534 Standard and Tools

The Ultimate (2024) Guide to J2534 Standard and Tools

Discover the transformative power of J2534 in 2024 for vehicle diagnostics and ECU programming with our comprehensive guide, offering detailed insight ...


Get in touch with us – We're ready to answer any and all questions.

* Mandatory fields

Email our engineers

We are here to help!