This document describes an extension to the Session Initiation Protocol (SIP). The purpose of this extension is to provide an extensible framework by which SIP nodes can request notification from remote nodes indicating that certain events have occurred. Concrete uses of the mechanism described in this document may be standardized in the future. Note that the event notification mechanisms defined herein are NOT intended to be a general-purpose infrastructure for all classes of event subscription and notification.
This document proposes the use of SIP for Network-capable appliances. It leverages the standard SIP capabilities to directly communicate with appliances even when they are behind firewalls, NATs or other entities that prevent direct end-to-end communication. When combined with the recently proposed Instant Messaging and Presence SIP extensions these techniques become even more powerful.
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SIP is very useful as a protocol for finding users and for rendezvous
with those users. It is also very good at getting status and presence
information which corresponds to those users (see the work of the PINT
WG, and recent SIP-based proposals for Instant Messaging (IM), and
Presence). This draft proposes using SIP with the SUBSCRIBE/NOTIFY
methods to carry message waiting status and message summaries from a
messaging system to an interested User Agent. This proposal contains
two message body definitions. The first is a simple text representation
suitable for giving the status of a single folder. The second uses XML;
it can carry status for multiple message folders within an account, it
is compatible with XSL style sheets, and it can be extended later
without breaking backwards compatibility.
This document proposes an extension to SIP for subscriptions and
notifications of user presence. Traditional SIP clients already make
use of the REGISTER method to upload presence state to network servers,
in order to enable call establishment. This extension allows that data
to be published to subscribers. This is accomplished by defining two
new SIP methods - SUBSCRIBE and NOTIFY, and by defining a new logical
entity, the presence agent (PA), which handles subscriptions and
This document defines a SIP extension (a single new method) that
supports Instant Messaging (IM).
This document proposes a simple SIP extension that allows presence
servers to query presence user agents for authorization for a
This document describes an XML based data format for conveying presence
information. The format is one instantiation of an abstract presence
data model also described here.
This document describes a data format, the Lightweight Presence
Information Data Format (LPIDF) for conveying presence information. The
format is based on RFC822 encoding of presence data. In fact, this
encoding is exactly identical to the encoding used by the Session
Initiation Protocol (SIP) in its registration messages. This simplifies
the process of parsing and processing presence data in clients which use
SIP for presence or communications services. LPIDF is one instantiation
of an abstract presence data model also described here.
Watchers are defined as entities that request (i.e., subscribe to)
presence information about a user. There is fairly complex state
associated with this subscription, and this state is dynamic. As a
result, it is possible, and indeed useful, to subscribe to the watcher
information for a particular subscriber. In order to enable this, a
format is needed to describe the state of watchers. This specification
describes an XML document format for such state.
This document defines an XML format for a buddy list, which represents a
list of other users a particular user would like to subscribe to. When
a presence client starts up, it needs to initiate subscriptions to the
users on the buddy list. By keeping this list in a standard XML format,
the list can be stored locally, or retrieved remotely using HTTP or any
other transfer protocol. The great advantage of storing it remotely is
that a user can move from machine to machine, fetch their buddy list
from a home server, and then subscribe to those users. This provides
personal mobility for presence services.
This document describes an extension to the Session Initiation Protocol
(SIP). The purpose of this extension is to provide a generic and
extensible framework by which SIP nodes can request notification from
remote nodes indicating that certain events have occured. Concrete uses
of the mechanism described in this document may be standardized in the
Last updated by Henning Schulzrinne