At a basic level, Active Directory (AD) bridging enables non-Windows systems to be joined to AD. Doing this allows Active Directory benefits to be extended consistently across Windows, Linux, and UNIX IT systems and network devices.
One key benefit is allowing administrators to log in to non-Windows systems using their dedicated AD login credentials instead of a local privileged account such as root, ec2-user, or ubuntu. As part of an identity consolidation best practice, this helps reduce the attack surface by avoiding the proliferation of multiple local accounts across IT systems and ensures full accountability of privileged activities by preventing the use of these anonymous shared, privileged accounts.
More advanced AD bridging capabilities include supporting complex multi-forest AD architectures and trust models, a hierarchical model for cross-platform role-based access control, deep AD service integrations (e.g., Kerberos, AD-DNS, and AD-CS), extending AD group policy to non-Windows platforms, and Windows smart card login configuration extended to Linux systems.
More AD Resources:
Blogs
Active Directory Bridging: If you're only using it for authentication, you're missing a ton of value
Active Directory Security and Hardening: An Ethical Hacker’s Guide to Reducing AD Risks
Securing Active Directory to Reduce Ransomware Attacks: A Quick Primer
Whitepapers
Advanced Active Directory Bridging
Active Directory Security and Hardening