About DAL OS Long Term Support firmware releases

A DAL OSDigi Accelerated Linux Operating System LTSLong Term Support firmware release is a version of firmware that is maintained for an extended period with a focus on stability, reliability, security, and critical bug fixes rather than new features. LTS releases are designed for production and enterprise environments where frequent or potentially disruptive updates are undesirable. LTS releases are delivered independently of the feature release cadence.

What it allows us to do

LTS firmware releases allow Digi to provide a stable, predictable firmware baseline that can be maintained over time with only critical security fixes and high-impact bug fixes, ensuring reliable long-term operation in production environments. LTS firmware releases are a foundational part of Digi’s firmware lifecycle strategy for DAL OS.

Each year, Digi publishes a production-qualified DAL OS LTS release based on a Linux LTS kernel. During the LTS lifecycle, Digi provides patch releases that address critical security vulnerabilities and high-impact defects while preserving existing behavior.

Why it matters to you

Separating DAL OS LTS releases from feature releases allows you to apply critical security and stability updates without introducing unexpected changes, while still giving you a clear and controlled path to adopt new features when it fits your needs. This approach reduces operational risk, supports predictable lifecycle planning, and improves security by limiting updates to essential fixes. At the same time, it provides deployment flexibility and simplifies validation and certification by maintaining a stable, consistent firmware baseline throughout the product lifecycle.

How LTS releases work

TS firmware releases provide a stable, production-ready baseline with a frozen feature set. During the support window, only security fixes, critical bug fixes, and reliability improvements are delivered, preserving consistent system behavior. Each LTS release is supported for a defined period, with one active LTS version at a time.

The following table highlights the key differences between LTS releases and firmware releases:

	LTS releases	Feature (non LTS) releases
Primary purpose	Long-term stability and maintenance	Rapid delivery of new features and enhancements
Release cadence	One per year	Multiple per year
Feature changes	Feature set is frozen after release	New features and functionality introduced
Security updates	Yes, throughout the support window	Yes, as part of regular releases
Update strategy	Periodic update to next annual LTS release	Update as new features become available

In simple terms

DAL OS LTS firmware releases are stable, long-term supported firmware versions designed for production use, where features are frozen and only critical security, bug, and reliability fixes are provided over time. They enable predictable, low-risk updates by separating ongoing maintenance from the introduction of new features.

DAL OS is the Linux-based operating system developed by Digi for its edge, IoT, and cellular devices.

Digi designates one major release per year. During that year, Digi may release LTS patch firmware as needed to address critical issues.

No. Once a release is designated as LTS, its feature set is frozen. New features are introduced only in feature - or non-LTS - releases and may be included in the next annual LTS release.

LTS patch releases may include:

• Security vulnerability fixes

• Critical or high-impact bug fixes

• Stability and reliability improvements

They do not introduce new features or functional enhancements.

Yes. You may migrate from a feature release to an LTS release when it aligns with your deployment, testing, and validation strategy.

After an LTS release reaches the end of its support window, Digi no longer provides maintenance updates for that release. You should upgrade to a newer supported LTS release to maintain security and support coverage.