1.1 Glossary
This document uses the following terms:
200 OK: A response to indicate that the request has succeeded.
address-of-record: A Session Initiation Protocol (SIP) URI that specifies a domain with a location service that can map the URI to another URI for a user, as described in [RFC3261].
Audio/Video Edge Server (A/V Edge Server): A protocol server that implements the Traversal Using Relay NAT (TURN) Extensions Protocol, as described in [MS-TURN]. The protocol server provides connectivity to a protocol client that is behind a network entity, if the network entity provides network address translation (NAT).
Augmented Backus-Naur Form (ABNF): A modified version of Backus-Naur Form (BNF), commonly used by Internet specifications. ABNF notation balances compactness and simplicity with reasonable representational power. ABNF differs from standard BNF in its definitions and uses of naming rules, repetition, alternatives, order-independence, and value ranges. For more information, see [RFC5234].
authentication: The act of proving an identity to a server while providing key material that binds the identity to subsequent communications.
caller: An endpoint that initiates a call to establish a media session.
Coordinated Universal Time (UTC): A high-precision atomic time standard that approximately tracks Universal Time (UT). It is the basis for legal, civil time all over the Earth. Time zones around the world are expressed as positive and negative offsets from UTC. In this role, it is also referred to as Zulu time (Z) and Greenwich Mean Time (GMT). In these specifications, all references to UTC refer to the time at UTC-0 (or GMT).
dial plan: The rules that govern the translation of dial strings into SIP and tel URIs, either global or local, as described in [RFC3966].
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.
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.
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.
long-term credentials: A set of user-authentication credentials that consist of a user name and password, and are used by a protocol client to authenticate with a protocol server.
Multipurpose Internet Mail Extensions (MIME): A set of extensions that redefines and expands support for various types of content in email messages, as described in [RFC2045], [RFC2046], and [RFC2047].
proxy: A computer, or the software that runs on it, that acts as a barrier between a network and the Internet by presenting only a single network address to external sites. By acting as a go-between that represents all internal computers, the proxy helps protects network identities while also providing access to the Internet.
QoE Monitoring Server: A server that collects and processes Quality of Experience (QoE) metrics.
Quality of Experience (QoE): A subjective measure of a user's experiences with a media service.
server: A computer on which the remote procedure call (RPC) server is executing.
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].
token: A word in an item or a search query that translates into a meaningful word or number in written text. A token is the smallest textual unit that can be matched in a search query. Examples include "cat", "AB14", or "42".
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].
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.
XML: The Extensible Markup Language, as described in [XML1.0].
XML schema: A description of a type of XML document that is typically expressed in terms of constraints on the structure and content of documents of that type, in addition to the basic syntax constraints that are imposed by XML itself. An XML schema provides a view of a document type at a relatively high level of abstraction.
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.