Hosted Messaging and Collaboration version 4.0 and previous solutions have shipped with two different and segmented user models, commonly known as the consumer model and the business model. These models applied to the way organizations and users were configured and granted permissions, how resources such as stores were allocated and the features available to users in each model.

In Hosted Messaging and Collaboration version 4.5, a new user model called Individual Information Worker (IIW) tenant model is introduced to take place of the previous consumer model. The Individual Information Worker is an individual that is unassociated with any hosted businesses. However, it has requirements similar to a typical business user including Mobility, full Outlook (MAPI) access, SharePoint site for collaboration with other Information Workers.

The following table summarizes some of the differences between the business model, consumer model and the IIW tenant model.

Feature	Business Organization	Consumer Organization	IIW Tenant Model
Users have access to other users within the same organization public details, for example, Phone Number and Email Address	Yes	No	Yes
Users can log on to MAPI clients including Microsoft Outlook	Yes	No	Yes
Users can log on to Outlook Web Access	Yes	Yes	Yes
Users can log on to POP or IMAP clients	Yes	Yes	Yes
Users can look up and view other users within the same organization, in the Outlook Global Address List. In this case of a Consumer or Individual user this may include friends and family or external contacts	Yes	No	Yes
Users can look up and view other users within the same organization, in the Outlook Web Access Address List. In this case of a Consumer or Individual user this may include friends and family or external contacts	Yes	No	Yes
Users can take advantage of other hosted services such as SharePoint	Yes	No	Yes
User can take advantage of any service on the platform including mobile access, Office Communications Server 2007 Services features and other future features	Yes	No	Yes

As is shown in the above table, IIW users will have the opportunity to take advantage of the same services available to business users, given the similarity in the model to the business model. This includes full MAPI access, Windows SharePoint Services sites or subsites, Mobility and Unified Messaging (OVA for example). They are also able to collaborate with friends and family through Outlook, OWA, SharePoint sites including WIKI, Blog and Photo Album sites, and their Windows Mobile phones.

As a result, it is recommended that the hosting classic consumer users take advantage of the IIW tenant model instead of the existing consumer model in HMC 4.5. However, we will not remove support for the consumer model from our API set.

• Individual Information Worker - This is an individual that is unassociated with any hosted businesses. It has requirements similar to those of a typical business user examples including Mobility, full Outlook (MAPI) access, SharePoint site for collaboration with other Information Workers.
  
• Tenant - This is an individual, company or group being hosted. In some ways a Tenant can be considered what an enterprise is in a non hosted model. However, a tenant may also be a container for a single Individual Information Worker.
  
• Friends and Family users - These are additional Individual Information Workers who are added to an IIW tenant by a tenant administrator.