domainlocking

Domain locking, also called domain-locking, is a software licensing technique that binds a licensed product to a specific network domain or organizational domain, limiting use to devices operating within that domain. By tying access to a domain name rather than to a device or user, vendors aim to prevent unauthorized redistribution or installation across unrelated networks. Domain locking can be implemented through license files containing domain constraints, online activation that validates the current domain against a licensing server, or runtime checks that verify the domain at startup and periodically during operation. Some systems bind to the DNS domain, while others tie the license to an Active Directory or corporate network domain. In offline environments, a domain-constrained key or a certificate issued for that domain may be required, with revalidation when connectivity allows.

Domain locking is most commonly used in enterprise software, where organizations seek to ensure that a license remains within a defined corporate boundary, and in certain software-as-a-service or content-distribution scenarios. It can also be used to enforce seat or installation caps within a domain.

Advantages of domain locking include reduced piracy, easier license management for IT teams, and the ability to enforce domain-specific terms. Limitations include sensitivity to domain changes such as mergers, domain migrations, or rebranding, potential disruption for remote or roaming users, and the risk of legitimate usage being blocked by misconfigurations. In practice, it is often used in combination with other controls, such as hardware identifiers or user authentication, and with online activation to mitigate offline circumvention. Related concepts include hardware-locked licensing, online activation, and digital rights management.