2026-02-02 –, Atlantis
Regular software updates continue to play a vital role in maintaining security, addressing CVEs, fixing bugs, and extending the lifespan of embedded Linux devices, especially in light of new regulatory requirements such as the EU Cyber Resilience Act (CRA). Dual A/B redundant update schemes remain widely used in industry and are supported by leading open source OTA solutions such as Mender, RAUC, and SWUpdate. However, certain use cases, including automotive systems, wearable devices and agricultural deployments in rural or remote environments, may face bandwidth limitations that make full-image updates less suitable. This session expands beyond traditional A/B systems by exploring delta update mechanisms integration in the Yocto Project and OpenEmbedded that aim to significantly reduce the amount of data transferred during each update.
A delta OTA update is a method that calculates and transfers only the differences between the currently installed software version and the new version, rather than downloading the entire image. The open source project libostree (previously known as OSTree) provides a Git-like, content-addressed filesystem and deployment mechanism that enables atomic, versioned and incremental system updates. It is used in Torizon OS in combination with Aktualizr, a C++ implementation of the Uptane OTA update client. Uptane is a secure software update framework designed for automobiles. Developers who want the security benefits of TUF but without the full complexity of Uptane may consider using Aktualizr-Lite, a streamlined build variant of the Aktualizr project used in the Linux microPlatform.
An alternative to delta updates that offers the same benefit of transferring only the necessary binary data is the concept of adaptive updates. Delta updates include the information required to move from one specific version to another, while adaptive updates do not rely on a particular starting version. Building on top of the classical A/B update scheme, RAUC provides advanced capabilities for HTTP streaming and adaptive updates, allowing the RAUC client on the embedded Linux device to download only the parts of an update bundle that are actually needed.
The talk will compared the advantages and disadvantages of the different open source source solutions while also cover integration considerations for the Yocto Project and OpenEmbedded. Attendees will gain a clear understanding of the technical differences between full A/B redundancy, delta updates and adaptive streaming updates. The goal is to provide engineers and developers with the insight needed to select an update strategy that aligns with the bandwidth constraints, storage limitations, security requirements and long-term support expectations of their embedded Linux devices.
Leon Anavi is an open source enthusiast and a senior software engineer at Konsulko Group. He is an active contributor to various Yocto/OpenEmbedded meta layers, Automotive Grade Linux (AGL) and many other open source projects. His professional experience includes web and mobile application development for various platforms as well as porting and maintaining embedded Linux distributions to Raspberry Pi and devices with x86-64, i.MX6, i.MX8, NVIDIA Tegra, RISC-V, Amlogic, Rockchip and Allwinner (aka sunxi) SoC. Leon holds a masters in Information Technology from the Technical University Sofia. His previous speaking experience includes talks about open source software and hardware during virtual and in-person events in San Francisco, San Diego, Portland (OR), Hong Kong, Shanghai, Shenzhen, Brussels, Lyon, Berlin, Edinburgh, London, Cambridge, Bratislava, Prague, Sofia and his hometown Plovdiv.