1.1 Glossary

This document uses the following terms:

200 OK: A response to indicate that the request has succeeded.

202 Accepted: A response that indicates that a request was accepted for processing.

403 Forbidden: A response that indicates that a protocol server understood but denies a request.

ActiveX control: A reusable software control, such as a check box or button, that uses ActiveX technology and provides options to users or runs macros or scripts that automate a task. See also ActiveX object.

Audio/Video Multipoint Control Unit (AVMCU): A Multipoint Control Unit (MCU) that supports audio-video (AV) conferencing.

Best Effort NOTIFY (BENOTIFY): A Session Initiation Protocol (SIP) method that is used to send notifications to a subscriber, as described in [MS-SIP]. Unlike the NOTIFY method, the BENOTIFY method does not require the recipient of the request to send a SIP response.

conference: A Real-Time Transport Protocol (RTP) session that includes more than one participant.

conference control command: See conference control request.

conference control request: A request that is sent by a conference client to modify a conference or the state of a conference participant.

conference store: A database that stores all of the conference-related information for an organization.

conference URI (conference-URI): A Session Initiation Protocol (SIP) URI that uniquely identifies the focus of a conference.

Content-Type header: A message header field whose value describes the type of data that is in the body of the message.

dialog: A peer-to-peer Session Initiation Protocol (SIP) relationship that exists between two user agents and persists for a period of time. A dialog is established by SIP messages, such as a 2xx response to an INVITE request, and is identified by a call identifier, a local tag, and a remote tag.

endpoint: A device that is connected to a computer network.

endpoint identifier (EPID): A unique identifier of a Session Initiation Protocol (SIP) endpoint. It is formed by combining the value of an epid parameter in a From or To header field with the address-of-record in the corresponding header field.

event package: A specification that defines a set of state information to be reported by a notifying Session Initiation Protocol (SIP) client to a subscriber. An event package also defines further syntax and semantics based on the framework that is required to convey such state information.

final response: A Session Initiation Protocol (SIP) response that terminates an SIP transaction. All 2xx, 3xx, 4xx, 5xx, and 6xx responses are final.

first-party request: A conference control request that modifies the state of the sending participant only.

focus: A single user agent that maintains a dialog and Session Initiation Protocol (SIP) signaling relationship with each participant, implements conference policies, and ensures that each participant receives the media that comprise the tightly coupled conference.

Focus Factory: A component that is responsible for creating, managing, and deleting conferences.

fully qualified domain name (FQDN): An unambiguous domain name that gives an absolute location in the Domain Name System's (DNS) hierarchy tree, as defined in [RFC1035] section 3.1 and [RFC2181] section 11.

Globally Routable User Agent URI (GRUU): A URI that identifies a user agent and is globally routable. A URI possesses a GRUU property if it is useable by any user agent client (UAC) that is connected to the Internet, routable to a specific user agent instance, and long-lived.

globally unique identifier (GUID): A term used interchangeably with universally unique identifier (UUID) in Microsoft protocol technical documents (TDs). Interchanging the usage of these terms does not imply or require a specific algorithm or mechanism to generate the value. Specifically, the use of this term does not imply or require that the algorithms described in [RFC4122] or [C706] must be used for generating the GUID. See also universally unique identifier (UUID).

Hypertext Transfer Protocol (HTTP): An application-level protocol for distributed, collaborative, hypermedia information systems (text, graphic images, sound, video, and other multimedia files) on the World Wide Web.

Hypertext Transfer Protocol Secure (HTTPS): An extension of HTTP that securely encrypts and decrypts web page requests. In some older protocols, "Hypertext Transfer Protocol over Secure Sockets Layer" is still used (Secure Sockets Layer has been deprecated). For more information, see [SSL3] and [RFC5246].

IM MCU: A Multipoint Control Unit (MCU) that supports Instant Messaging (IM) conferencing.

in-band provisioning: A process in which a protocol client obtains configuration information from a protocol server.

Internet Protocol version 4 (IPv4): An Internet protocol that has 32-bit source and destination addresses. IPv4 is the predecessor of IPv6.

Internet Protocol version 6 (IPv6): A revised version of the Internet Protocol (IP) designed to address growth on the Internet. Improvements include a 128-bit IP address size, expanded routing capabilities, and support for authentication and privacy.

INVITE: A Session Initiation Protocol (SIP) method that is used to invite a user or a service to participate in a session.

lobby: A collection of objects that contains data about one or more participants who are waiting for the organizer or a presenter in a conference to admit participants to the conference.

MCU-Conference-URI: A literal that specifies a URI that can be used to access conferencing services in the context of a Multipoint Control Unit (MCU).

MCU-Type: A literal that identifies all of the media types, such as audio-video, that are supported by a Multipoint Control Unit (MCU).

mixer: An intermediate system that receives a set of media streams of the same type, combines the media in a type-specific manner, and redistributes the result to each participant.

Multipoint Control Unit (MCU): A server endpoint that offers mixing services for multiparty, multiuser conferencing. An MCU typically supports one or more media types, such as audio, video, and data.

notification: A process in which a subscribing Session Initiation Protocol (SIP) client is notified of the state of a subscribed resource by sending a NOTIFY message to the subscriber.

notify: The process of sharing presence information with subscribed client devices by using the Wide Area Network Device Presence Protocol (WAN DPP).

organizer: The owner or creator of a meeting or appointment.

participant: A user who is participating in a conference or peer-to-peer call, or the object that is used to represent that user.

public switched telephone network (PSTN): Public switched telephone network is the voice-oriented public switched telephone network. It is circuit-switched, as opposed to the packet-switched networks.

service: A process or agent that is available on the network, offering resources or services for clients. Examples of services include file servers, web servers, and so on.

Session Description Protocol (SDP): A protocol that is used for session announcement, session invitation, and other forms of multimedia session initiation. For more information see [MS-SDP] and [RFC3264].

Session Initiation Protocol (SIP): An application-layer control (signaling) protocol for creating, modifying, and terminating sessions with one or more participants. SIP is defined in [RFC3261].

SIP message: The data that is exchanged between Session Initiation Protocol (SIP) elements as part of the protocol. An SIP message is either a request or a response.

SIP request: A Session Initiation Protocol (SIP) message that is sent from a user agent client (UAC) to a user agent server (UAS) to call a specific operation.

SIP response: A Session Initiation Protocol (SIP) message that is sent from a user agent server (UAS) to a user agent client (UAC) to indicate the status of a request from the UAC to the UAS.

subscribe: The process of registering to receive updates about presence information for client devices. The updates are delivered by using Wide Area Network Device Presence Protocol (WAN DPP).

subscription: The result of a SUBSCRIBE request from a Session Initiation Protocol (SIP) element.

third-party request: A conference control request that modifies the state of participants other than the participant who sent the request.

Transmission Control Protocol (TCP): A protocol used with the Internet Protocol (IP) to send data in the form of message units between computers over the Internet. TCP handles keeping track of the individual units of data (called packets) that a message is divided into for efficient routing through the Internet.

Transport Layer Security (TLS): A security protocol that supports confidentiality and integrity of messages in client and server applications communicating over open networks. TLS supports server and, optionally, client authentication by using X.509 certificates (as specified in [X509]). TLS is standardized in the IETF TLS working group.

Uniform Resource Identifier (URI): A string that identifies a resource. The URI is an addressing mechanism defined in Internet Engineering Task Force (IETF) Uniform Resource Identifier (URI): Generic Syntax [RFC3986].

Uniform Resource Locator (URL): A string of characters in a standardized format that identifies a document or resource on the World Wide Web. The format is as specified in [RFC1738].

user agent client (UAC): A logical entity that creates a new request, and then uses the client transaction state machinery to send it. The role of UAC lasts only for the duration of that transaction. In other words, if a piece of software initiates a request, it acts as a UAC for the duration of that transaction. If it receives a request later, it assumes the role of a user agent server (UAS) for the processing of that transaction.

user agent server (UAS): A logical entity that generates a response to a Session Initiation Protocol (SIP) request. The response either accepts, rejects, or redirects the request. The role of the UAS lasts only for the duration of that transaction. If a process responds to a request, it acts as a UAS for that transaction. If it initiates a request later, it assumes the role of a user agent client (UAC) for that transaction.

UTF-8: A byte-oriented standard for encoding Unicode characters, defined in the Unicode standard. Unless specified otherwise, this term refers to the UTF-8 encoding form specified in [UNICODE5.0.0/2007] section 3.9.

X.509: An ITU-T standard for public key infrastructure subsequently adapted by the IETF, as specified in [RFC3280].

MAY, SHOULD, MUST, SHOULD NOT, MUST NOT: These terms (in all caps) are used as defined in [RFC2119]. All statements of optional behavior use either MAY, SHOULD, or SHOULD NOT.