What Is Enhanced Presence?
Presence is a concept that encapsulates information about how available users are and what they are doing in order to help establish real-time communications. Client applications using presence can help users decide whether and how they should contact other remote users. These applications can increase the effectiveness of user communication by combining presence information and business-specific information about the individuals who need to communicate.
Enhanced presence in Office Communicator 2007 and Unified Communications adds features that use sophisticated techniques to determine presence information and that give users control over who can view that presence information. These enhanced presence features that are described in the Office Communicator 2007: The Enhanced Presence Model white paper. They are:
- Complex presence states that can be automatically detected and can transition from Available to Inactive to Away.
- Aggregation of the presence states published by any user from multiple endpoints, such as Outlook calendar data, phone states, and machine states.
- Control of interruptions by setting the presence to the Do Not Disturb status.
- Integration with Office applications such as Outlook and SharePoint.
- Access levels that enable users to control the level of presence information that others see.
- Access to calendar information and services.
Office Communicator is built on the Unified Communications platform and uses enhanced presence through a publication and subscription model. Data is organized into categories and published in containers that provide levels of access. Through the Unified Communications platform, Office Communicator publishes data to an Office Communications Server, which in turn sends the data to clients who have subscribed to the categories and who are members of the containers that have been specified by the publisher.
It is important to understand that presence data is defined by the client applications, and Office Communications Server does not have any awareness of how clients make use of the presence data. Office Communicator publishes and subscribes to specific data categories with specific containers, and custom applications can use those data categories and containers if they want to interact with Office Communicator. However, they also have the option of using different data categories and containers if they want to operate independently of Office Communicator. Developers using Unified Communications should have an understanding of which categories and containers Office Communicator uses so that their custom applications can either take advantage of the enhanced presence features that Office Communicator offers, or at the minimum, to avoid publishing data that interferes with the operation of Office Communicator.