A multisite ATG environment is one in which a single instance of ATG products supports more than one Web site, and the sites are configured to share resources such as a shopping cart. As an example, an apparel manufacturer could have two brands, one for clothing and one for shoes. Each brand could have its own Web site, but the shopping cart could be shared between the two sites, allowing cross-selling opportunities such as the ability to give promotions for one site based on items purchased at the other.

In a multisite environment, user profiles are automatically shared across all your Web sites. The same external and internal profile repositories are used in all cases; there is no option to set up separate profile repositories for each site you support.

It is important to be aware of the implications of this behavior in regard to registration and login. When a user registers at any one of your sites, a persistent profile is created for him or her and added to the external profile repository. However, because the repository is not site aware, the registration is not specific to Site A. Users who register at Site A are effectively registered at Site B as well. If you require login credentials to access your sites, the user is automatically permitted to log into both Site A and Site B and can do so using the same username and password. A user who logs into Site A simultaneously logs into Site B.

Mechanisms such as targeting rules and scenarios that manage the display of dynamic, personalized content can be configured to be site aware, which means you can display specific content to individual users according to their current site. For example, you could set up a scenario that waits for users to register on Site A and displays them personalized content. However, as stated above, the profiles themselves are the same for all sites.

For information on configuring your environment for multisite support, refer to the ATG Multisite Administration Guide. For more information on the multisite features available in targeting rules, scenarios, and other personalization mechanisms, see the ATG Personalization Guide for Business Users and the chapters for those features later in this guide.