Another big advantage of Password Sentry is Interlinking. What is Interlinking? Interlinking is a really cool feature, and one that is unique to Password Sentry. None of our competitors offer this functionality. Interlinking Plugin allows you to grant access from another secure area on one domain using the plugin to the secure area on another domain also using the plugin. Interlinking sites can be on the same server or different servers. This enhanced function allows for cross-domain secure areas sharing. Members of one site can access the members area of another site, and vice versa. The interlinking can be one-way or two-way. GREAT cross-promotional tool. This function has become VERY popular with many of our adult paysite clients who apply it in partnership with other sites to give themselves a competitive edge in these difficult times. All sites, however, MUST be using Password Sentry and the optional PHP Authentication Plugin. This handshaking protocol between multiple domains and servers is VERY SECURE. The plugin is NOT referrer-based, and as such, is NOT vulnerable to referrer spoofing! Very EASY to setup: completed configured and implemented via the Password Sentry web-based Admin Control Panel (ACP). Just another way Password Sentry stays ahead of the competition!