FAQs- eSync Technology

What is eSync?
eSync is an over-the-air technology for software updating and data gathering from a connected vehicle. Any number of electronic devices, from multiple vendors, over multiple networks and busses, running a variety of operating systems, can be accessed by the secure eSync data pipeline.
What makes eSync technology different?

eSync technology uses a structured approach of distributed software agents with defined and published APIs (programming interfaces). The architecture encourages multi-company participation in constructing a standardized bidirectional OTA data pipeline. The eSync Alliance provides extensive specifications for any member company to implement their own eSync compliant portion of the data pipeline.

How is eSync architected?
eSync technology uses a Server-Client-Agent architecture to reach from the cloud, through a vehicle gateway, to any number of individual ECUs or smart sensors. The Server software resides in a public or private cloud. There is typically one software Client per vehicle, located in a telematics unit, infotainment head unit, or vehicle gateway. Agents are distributed throughout the vehicle for the various devices (ECUs, smart sensors, etc.), and may be resident in the devices or at nearby network nodes where processing and memory is available for the Agent software.
Does eSync require specific hardware?
No. eSync technology is an all-software specification. Hardware requirements are general – microprocessor or microcontroller processing resources and memory.
Does eSync require a specific operating system?
No. eSync technology specifications define the architecture, functional behavior and interfaces of the Server, Client and Agents. These can be implemented in any operating system. To date eSync software components have been implemented for Android, Linux, QNX, AUTOSAR, Integrity and a variety of small real time operating systems including Erika, FreeRTOS and others.
Does eSync work on a specific cloud infrastructure?

The eSync specifications do not bind the eSync Server to any particular cloud infrastructure. Implementations can be cloud-specific or cloud-agnostic.  To date eSync Servers have been deployed on 4 public clouds worldwide, as well as OEM private clouds.

How does eSync support numerous devices in the vehicle?

The eSync architecture uses Agents distributed throughout the in-vehicle network, to do the majority of update tasks.  These Agents can reside in the edge devices (domain master ECUs, ECUs, smart sensors), or can be placed on network nodes near to the edge devices that they update.  Updates to many devices are processed in parallel by these numerous Agents, so that vehicle downtimes are effectively minimized.  Agents are customized to the devices they serve, allowing integration of diverse devices with differing resources, operating systems, flash mechanisms and data generation capabilities into a common data pipeline. 

How does eSync gather data from edge devices?

eSync data gathering is covered in section 8 of the eSync Specifications v2.0.  Automakers can extract data from an ECU in the form of short message data, bulk diagnostic data or streaming data (from cameras and/or LiDARs, for example).  eSync can also deploy diagnostic scripts from the eSync Server to the edge device, allowing use of a command interface to initiate and terminate the gathering of ECU-specific data useful for remote debugging.

How does eSync support safety domain updates?

The eSync data pipeline makes use of the construct of “policy” in the processes of updating devices.  Policy can differ for devices and domains throughout the vehicle.  Agents for safety-critical devices can implement more stringent policies regarding what state the vehicle must be in before updates begin, how rollback occurs in event of failure, and can even implement more stringent security.  Also software updates can make use of policies defining dependent relationships, so that full software integrity can be assured when updating safety systems comprised of multiple devices.

How does eSync manage updating of multiple dependent devices?

Within the eSync platform software for different devices can be bundled into “packages”, with dependencies and sequences-of-installation defined as a policy of the package. If any software component in the package is not successfully installed, then the entire package is identified as a failed update, and all devices are rolled back to their last valid software.

Does eSync use Delta Compression?

eSync specifications support, but do not require, the use of delta compression.  Most commercial deployments of eSync to date have used delta compression to reduce wireless bandwidth consumption.

Has eSync seen commercial deployments?

Yes.  The first vehicles deployed with eSync OTA began shipping in the spring of 2019. In these luxury SUVs eSync is used to update 33 separate electronic devices. By the beginning of 2021, five automakers from Europe, China and Japan had adopted eSync OTA for production vehicles, forecasting that 13 million vehicles with eSync OTA will be on the roads in the near future.


Membership in the eSync Alliance is open to all companies. OEMs, Tier1s, software and hardware vendors, and cloud service providers are welcome to participate in the eSync Platform. Membership in the eSync Alliance gives you the opportunity to collaborate with other members in the eSync ecosystem.