SIMPLE is an extension of Session Initiation Protocol (SIP) that allows presence and Instant Messaging (IM) to become just additional components in an overall communications system that allows voice, video, application sharing, and messaging, all of which are linked by presence. In contrast to the vast majority of IM software deployed today, SIMPLE is an open standard.

An open standard, protocol used for Instant Messaging (IM). IMis the real time transfer of messages between users. These short messages are used in conversational mode, transferring messages back and forth as fast as the users can type, allowing them to maintain an interactive conversation. SIMPLE is the message method, an extension of Session Initiation Protocol (SIP). It allows the transfer of Instant Messages.

Being that a message request is an extension of SIP, it will contain all the security features and request routing of SIP. Message requests, which carry content in the form of Multipurpose Internet Mail Extensions (MIME) body parts, do not initiate SIP sessions dialogs on their own. Each Instant Message is stand alone, just like individual paper notes. Message requests are sent in the context of a dialog that has been initiated by some other SIP request.

The Internet Engineering Task Force’s (IETF) SIMPLE working group, in the applications area, is chartered to specify a set of profiles and extensions to SIP in order to enable IM/presence. The group has produced an extensive set of Internet drafts and has published a proposed standard. The IM and Presence Protocol working group of the IETF has published the general requirements for and model of IM/presence as RFCs 2778 and 2779. The basics of the proposed protocol have been widely implemented.

Other Related Quotes for SIMPLE

“…SIMPLE backers extol the broad media possibilities of a SIP-based signaling protocol with natural affinities for voice, video, and conferencing. XMPP proponents, on the other hand, tout an XML-based data transport technology that is built to manage IM and presence.” [Cathleen Moore, InfoWorld]

“…Instant messaging/presence is at an inflection point today. The lack of standards-based interoperable IM/presence systems makes it difficult for IT to control and monitor deployment of this popular business tool. Proprietary networks and protocols also impede IM users from communicating with others outside their organizations. What’s needed is a unified protocol that enables IM/presence, just as Simple Mail Transfer Protocol, HTTP and Real-Time Protocol (RTP) do for e-mail, Web and voice traffic. The solution is Session Initiation Protocol for IM and Presence Leveraging Extensions (SIMPLE ).” [Scott Petrack - Network World]

“…SIMPLE Instant Messaging provides a standard portable and secure interface to exchange messages between SIMPLE clients. SIMPLE is an extension of SIP to support presence and instant messaging.” [Java Community Process]

“…SIMPLE is a protocol that remains largely undefined. It is currently a set of proposed guidelines for how to build software extensions on top of the SIP platform. Until final ratification of these guidelines, some of the proposals have general industry acceptance and some are still open to debate.” [ACM, Inc.]

More on SIP

The Session Initiation Protocol forms the basis of an Internet-centric multimedia communications architecture. SIP establishes sessions over IP networks for people wishing to communicate. In this context, a session is any interactive communication that takes place between two or more entities over an IP network, from a simple two-way telephone call or an instant message exchange, to a collaborative multimedia conference session. SIP is a Web paradigm protocol standardized by the Internet Engineering Task Force (IETF). It’s similar to the two major Internet protocols—HTTP (World Wide Web) and SMTP (e-mail)—in that it uses symbolic addresses to represent people who wish to communicate.

SIP enables converged voice and multimedia services such as voice-enriched eCommerce, Web page click-to-dial, instant messaging with buddy lists, and much more. SIP session management is the key to enabling IP-based natural communications between people, not devices. By using SIP, users may locate and contact one another—regardless of media content or number of participants—using disparate computers, phones, televisions and hand-held devices.

SIP was developed to serve as a mechanism to establish a wide variety of sessions. Therefore, SIP does not dictate the details within a session but instead negotiates interaction based on the capabilities of participants. This simplicity means that SIP is scalable, extensible and fits comfortably into different architectures and deployment scenarios.

History

SIP emerged in the mid-1990s from research conducted at Columbia University in an effort to standardize a method for inviting participants from other universities to large-scale multimedia conferences. As it was developed, it became apparent that the protocol was much more flexible than anyone expected. The IETF—the body responsible for administering and developing the mechanisms that comprise the Internet—adopted SIP as the standard protocol for establishing and terminating multimedia sessions in 1999.

Capabilities

SIP is a control protocol that initiates, modifies, and terminates communication sessions with one or more participants. The protocol enables participants to agree on a set of compatible media types and supports user mobility by proxying and redirecting requests to any user’s current location. SIP enables the following functions:

• Name translation and user location—Allows people to find each other without knowing the details of each others’ device addresses or physical locations.

• Media negotiation—Handles negotiations that enable all participants in a session to agree on common media and the technology details involved—including voice, video, audio, instant messaging, applications data exchange or any combination thereof.

• Session participant management—Manages the adding, dropping or transferring of participants.

• Session feature changes—Allows for changing the media used in a session while the session is in progress.