Service plans represent a convenient way to assemble and productize the Microsoft Exchange Server 2007 features made available to a user. The Hosted Exchange environment provides several sample service plans, and the service provider can configure more.
In creating a service plan, the service provider chooses the features they wish to add to a plan and assembles them using a procedure called CreateMailboxPlan. If a desired feature is not available, a procedure called CreateFeatureType lets you create features which can be added to plans.
When provisioning a new business organization, the provisioning process includes selecting which service plans are available to users within that organization. If it becomes necessary to modify what plans are available to the organization, the AddAvailablePlans procedure can be used.
When a plan is assigned to a user, Microsoft Provisioning System (MPS) needs to know all the feature type information so it can make necessary adjustments in Exchange. It is important to understand the manual process that takes place within Active Directory directory service and Exchange mailboxes.