The Presence Is Now! SIP supports a new model for communications through its use of the Extensible Messaging and Presence Protocol (XMPP, which can also be used for presence) and SIP for Instant Messaging and Presence Leveraging Extensions (or more simply, SIMPLE). Both are widely adopted open protocol standards defined by the IETF. In an intelligent communications network, people can specify their communications preferences and availability. This feature is known as presence — an intelligent “network overlay” that makes it easier for a calling party to reach an available and willing-to-be-called party. Presence enables people to inform others of their status, their availability, and how they can be contacted before a communication session even begins, thereby increasing productivity by making it easier to reach people more efficiently. Many devices can provide presence information, which is particularly powerful when integrated across all of a person’s communication devices, such as IP phones, mobile phones, softphones, wireless devices, and PDAs. Presence is not limited to a single person; it can also apply to a group of people (for example, “Finance”) or a device (for example, Phone Status = “Off-hook” or “On-hook”). Even more exciting, both people and applications can access presence information, providing the opportunity to create next-generation converged communication applications. For example, your network can deliver new capabilities such as polite calling (calls that are less disruptive for the party being called) — based on information from her calendar application, calls to an executive can automatically be routed to an assistant if the executive is busy. This can eliminate the need for the caller to leave a voice mail and allows the executive to stay focused on her current meeting.