Which directory service would you recommend for a multinational corporation to allow interoperability amongst various vendors?

The Lightweight Directory Access Protocol (LDAP) is the recommended choice for a multinational corporation seeking to ensure interoperability among various vendor systems. LDAP is an open, vendor-neutral protocol that facilitates access to directory services, making it adaptable for different environments and systems. It allows for seamless communication and integration across platforms and applications from various vendors.

Its design supports a hierarchical structure and is based on industry standards, enabling smooth interaction and information exchange regardless of the underlying technologies used by different organizations or software vendors.

In contrast, while X.500 provides a robust and comprehensive directory service, it is less commonly used in modern implementations compared to LDAP, which specifically addresses interoperability needs. Active Directory, while prevalent in Windows environments, is more proprietary and optimized for Microsoft technology stacks, which can limit cross-vendor integrations. Novell Directory Services (NDS), although historically significant, is also less prevalent today and lacks the universal compatibility that LDAP offers. Therefore, for a multinational setup requiring diverse vendor collaboration, LDAP is the superior option.