it was established in 2011 as a formal initiative. v4.4 is supported for 6 years (or longer, up to 10 years Super Long-Term Support). Commercial releases such as Ubuntu support 5 years LTS with a release cadence of 2 years which is typically enough to bring a product to market without having to switch os releases halfway development or initial deployment. Roll your own versus commercial grade Roll Your Own (RYO) Linux means that you build your own Linux distribution from source/ scratch including maintenance. This includes optional selection of which desktop [Graphical User Interface (GUI)] and software packages (applications and/or services) are to be included in the file system, allowing to tune the Linux image to the application. Projects such as Yocto help developers in the process of building (embedded) Linux systems for many hardware architectures and are supported by hardware vendors as an "out of the box" os that is sup- plied with evaluation boards and commercial hardware. A Linux distribution (or "distro") is made from a software collection that is based upon a Linux kernel and a package management system to define the software packages to be installed. Distros can be free-of-charge or commercially backed and are available tuned for a variety of systems-from embedded devices (OpenWrt is widely used in Wi-Fi routers) to personal computers (e.g., Ubuntu). A typical Linux distribution includes the kernel, tools and libraries, a desktop environment, and SO on. It also comes with the piece of mind of having a support infrastructure and a level of security given that any security issues found will be fixed and shared across many customers, as well as having a solution that is protected against liabilities including potential IPR protection. Some commercial grade Linux distributions include support for specific features as required in telecommunication systems such as real- time (RT) support (see Section 5.1.5) and networking stack optimizations. Realtime and timing As we explained, Linux has gained popularity