SIMPLE

The Message Session Relay Protocol (MSRP) defines a mechanism for sending instant messages (IMs) within a peer-to-peer session, negotiated using the Session Initiation Protocol (SIP) and the Session Description Protocol (SDP). This document defines the necessary tools for establishing multi-party chat sessions, or chat rooms, using MSRP.

The IETF has produced many specifications related to Presence and Instant Messaging with the Session Initiation Protocol (SIP). Collectively, these specifications are known as SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE). This document serves as a guide to the SIMPLE suite of specifications. It categorizes the specifications, explains what each is for, and how they relate to each other.

This document defines a Message Session Relay Protocol (MSRP) extension, Connection Establishment for Media Anchoring (CEMA). Support of this extension is OPTIONAL. The extension allows middleboxes to anchor the MSRP connection, without the need for middleboxes to modify the MSRP messages; thus, it also enables secure end-to-end MSRP communication in networks where such middleboxes are deployed. This document also defines a Session Description Protocol (SDP) attribute, 'msrp-cema', that MSRP endpoints use to indicate support of the CEMA extension. [STANDARDS-TRACK]

This document defines an alternative connection model for Message Session Relay Protocol (MSRP) User Agents (UAs); this model uses the connection-oriented media (COMEDIA) mechanism in order to create the MSRP transport connection. The model allows MSRP UAs behind Network Address Translators (NATs) to negotiate which endpoint initiates the establishment of the Transmission Control Protocol (TCP) connection, in order for MSRP messages to traverse the NAT. [STANDARDS-TRACK]

This specification defines a document format that can be used to indicate that a change has occurred in a document managed by the Extensible Markup Language (XML) Configuration Access Protocol (XCAP). This format reports which document has changed and its former and new entity tags. It can report the differences between versions of the document, using an XML patch format. It can report existing element and attribute content when versions of an XCAP server document change. XCAP diff documents can be delivered to diff clients using a number of means, including a Session Initiation Protocol (SIP) event package. [STANDARDS-TRACK]

Instant Messaging (IM) refers to the transfer of messages between users in real-time. This document provides a mechanism whereby endpoints can request Instant Message Disposition Notifications (IMDN), including delivery, processing, and display notifications, for page-mode instant messages.

The Common Presence and Instant Messaging (CPIM) data format specified in RFC 3862 is extended with new header fields that enable endpoints to request IMDNs. A new message format is also defined to convey IMDNs.

This document also describes how SIP entities behave using this extension. [STANDARDS-TRACK]

Presence Information Data Format (PIDF) defines a common presence data format for Common Profile for Presence (CPP) compliant presence protocols. This memo defines a PIDF extension to represent SIP User Agent capabilities. [STANDARDS-TRACK]

Extensible Markup Language (XML) documents are widely used as containers for the exchange and storage of arbitrary data in today's systems. In order to send changes to an XML document, an entire copy of the new version must be sent, unless there is a means of indicating only the portions that have changed. This document describes an XML patch framework utilizing XML Path language (XPath) selectors. These selector values and updated new data content constitute the basis of patch operations described in this document. In addition to them, with basic <add>, <replace>, and <remove> directives a set of patches can then be applied to update an existing XML document. [STANDARDS-TRACK]

The Presence Information Document Format (PIDF) specifies the baseline XML-based format for describing presence information. One of the characteristics of the PIDF is that the document always needs to carry all presence information available for the presentity. In some environments where low bandwidth and high latency links can exist, it is often beneficial to limit the amount of transported information over the network. This document introduces a new MIME type that enables transporting of either only the changed parts or the full PIDF-based presence information. [STANDARDS-TRACK]

By default, presence delivered using the presence event package for the Session Initiation Protocol (SIP) is represented in the Presence Information Data Format (PIDF). A PIDF document contains a set of elements, each representing a different aspect of the presence being reported. When any subset of the elements change, even just a single element, a new document containing the full set of elements is delivered. This memo defines an extension allowing delivery of only the presence data that has actually changed. [STANDARDS-TRACK]

The Session Initiation Protocol (SIP) Extension for Event State Publication describes a mechanism with which a presence user agent is able to publish presence information to a presence agent. Using the Presence Information Data Format (PIDF), each presence publication contains full state, regardless of how much of that information has actually changed since the previous update. As a consequence, updating a sizeable presence document with small changes bears a considerable overhead and is therefore inefficient. Especially with low bandwidth and high latency links, this can constitute a considerable burden to the system. This memo defines a solution that aids in reducing the impact of those constraints and increases transport efficiency by introducing a mechanism that allows for publication of partial presence information. [STANDARDS-TRACK]

Authorization is a key function in presence systems. Authorization policies, also known as authorization rules, specify what presence information can be given to which watchers, and when. This specification defines an Extensible Markup Language (XML) document format for expressing presence authorization rules. Such a document can be manipulated by clients using the XML Configuration Access Protocol (XCAP), although other techniques are permitted. [STANDARDS-TRACK]

This document describes the Message Session Relay Protocol, a protocol for transmitting a series of related instant messages in the context of a session. Message sessions are treated like any other media stream when set up via a rendezvous or session creation protocol such as the Session Initiation Protocol. [STANDARDS-TRACK]

Two separate models for conveying instant messages have been defined. Page-mode messages stand alone and are not part of a Session Initiation Protocol (SIP) session, whereas session-mode messages are set up as part of a session using SIP. The Message Session Relay Protocol (MSRP) is a protocol for near real-time, peer-to-peer exchanges of binary content without intermediaries, which is designed to be signaled using a separate rendezvous protocol such as SIP. This document introduces the notion of message relay intermediaries to MSRP and describes the extensions necessary to use them. [STANDARDS-TRACK]

This specification defines the Extensible Markup Language (XML) Configuration Access Protocol (XCAP). XCAP allows a client to read, write, and modify application configuration data stored in XML format on a server. XCAP maps XML document sub-trees and element attributes to HTTP URIs, so that these components can be directly accessed by HTTP. [STANDARDS-TRACK]

In multimedia communications, presence, and instant messaging systems, there is a need to define Uniform Resource Identifiers (URIs) that represent services that are associated with a group of users. One example is a resource list service. If a user sends a Session Initiation Protocol (SIP) SUBSCRIBE message to the URI representing the resource list service, the server will obtain the state of the users in the associated group, and provide it to the sender. To facilitate definition of these services, this specification defines two Extensible Markup Language (XML) documents. One document contains service URIs, along with their service definition and a reference to the associated group of users. The second document contains the user lists that are referenced from the first. This list of users can be utilized by other applications and services. Both documents can be created and managed with the XML Configuration Access Protocol (XCAP). [STANDARDS-TRACK]

This document describes a usage of the Extensible Markup Language (XML) Configuration Access Protocol (XCAP) for manipulating the contents of Presence Information Data Format (PIDF) based presence documents. It is intended to be used in Session Initiation Protocol (SIP) based presence systems, where the Event State Compositor can use the XCAP-manipulated presence document as one of the inputs on which it builds the overall presence state for the presentity. [STANDARDS-TRACK]

The SIP event notification framework describes the usage of the Session Initiation Protocol (SIP) for subscriptions and notifications of changes to the state of a resource. The document does not describe a mechanism whereby filtering of event notification information can be achieved.

This document describes the operations a subscriber performs in order to put filtering rules associated with a subscription to event notification information in place. The handling, by the subscriber, of responses to subscriptions carrying filtering rules and the handling of notifications with filtering rules applied to them are also described. Furthermore, the document conveys how the notifier behaves when receiving such filtering rules and how a notification is constructed. [STANDARDS-TRACK]

The SIP event notification framework describes the usage of the Session Initiation Protocol (SIP) for subscriptions and notifications of changes to a state of a resource. The document does not describe a mechanism whereby filtering of event notification information can be achieved. Filtering is a mechanism for defining the preferred notification information to be delivered and for specifying triggers that cause that information to be delivered. In order to enable this, a format is needed to enable the subscriber to describe the state changes of a resource that cause notifications to be sent to it and what those notifications are to contain. This document presents a format in the form of an XML document. [STANDARDS-TRACK]

This document presents an extension to the Session Initiation Protocol (SIP)-Specific Event Notification mechanism for subscribing to a homogeneous list of resources. Instead of sending a SUBSCRIBE for each resource individually, the subscriber can subscribe to an entire list and then receive notifications when the state of any of the resources in the list changes. [STANDARDS-TRACK]

This document defines the underlying presence data model used by Session Initiation Protocol (SIP) for Instant Messaging and Presence Leveraging Extensions (SIMPLE) presence agents. The data model provides guidance on how to map various communications systems into presence documents in a consistent fashion. [STANDARDS-TRACK]

The Presence Information Data Format (PIDF) defines a basic format for representing presence information for a presentity. This format defines a textual note, an indication of availability (open or closed) and a Uniform Resource Identifier (URI) for communication. The Rich Presence Information Data format (RPID) described here is an extension that adds optional elements to the Presence Information Data Format (PIDF). These extensions provide additional information about the presentity and its contacts. The information is designed so that much of it can be derived automatically, e.g., from calendar files or user activity.

This extension includes information about what the person is doing, a grouping identifier for a tuple, when a service or device was last used, the type of place a person is in, what media communications might remain private, the relationship of a service tuple to another presentity, the person's mood, the time zone it is located in, the type of service it offers, an icon reflecting the presentity's status, and the overall role of the presentity.

These extensions include presence information for persons, services (tuples), and devices. [STANDARDS-TRACK]

The Presence Information Data Format (PIDF) defines a basic XML format for presenting presence information for a presentity. This document extends PIDF, adding a timed status extension (<timed-status> element) that allows a presentity to declare its status for a time interval fully in the future or the past. [STANDARDS-TRACK]

The Presence Information Data Format (PIDF) defines a basic XML format for presenting presence information for a presentity. The Contact Information for the Presence Information Data format (CIPID) is an extension that adds elements to PIDF that provide additional contact information about a presentity and its contacts, including references to address book entries and icons. [STANDARDS-TRACK]

In instant messaging (IM) systems, it is useful to know during an IM conversation whether the other party is composing a message; e.g., typing or recording an audio message. This document defines a new status message content type and XML namespace that conveys information about a message being composed. The status message can indicate the composition of a message of any type, including text, voice, or video. The status messages are delivered to the instant messaging recipient in the same manner as the instant messages themselves. [STANDARDS-TRACK]

This document describes the usage of the Session Initiation Protocol (SIP) for subscriptions and notifications of presence. Presence is defined as the willingness and ability of a user to communicate with other users on the network. Historically, presence has been limited to "on-line" and "off-line" indicators; the notion of presence here is broader. Subscriptions and notifications of presence are supported by defining an event package within the general SIP event notification framework. This protocol is also compliant with the Common Presence Profile (CPP) framework. [STANDARDS-TRACK]

This document defines the watcher information template-package for the Session Initiation Protocol (SIP) event framework. Watcher information refers to the set of users subscribed to a particular resource within a particular event package. Watcher information changes dynamically as users subscribe, unsubscribe, are approved, or are rejected. A user can subscribe to this information, and therefore learn about changes to it. This event package is a template-package because it can be applied to any event package, including itself. [STANDARDS-TRACK]

Watchers are defined as entities that request (i.e., subscribe to) information about a resource. There is fairly complex state associated with these subscriptions. The union of the state for all subscriptions to a particular resource is called the watcher information for that resource. This state is dynamic, changing as subscribers come and go. As a result, it is possible, and indeed useful, to subscribe to the watcher information for a particular resource. In order to enable this, a format is needed to describe the state of watchers on a resource. This specification describes an Extensible Markup Language (XML) document format for such state. [STANDARDS-TRACK]