Medias Mediatrix 1204, Справочное руководство

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Plain Old Telephone System (POTS) Reference Manual (SIP Version)
Mediatrix 1204 343
Plain Old Telephone System (POTS)
Standard telephone service used by most residential locations; basic service supplying standard single line
telephones, telephone lines, and access to the public switched network.
Port
Network access point, the identifier used to distinguish among multiple simultaneous connections to a host.
Portable Operating System Interface (POSIX)
POSIX is a set of standard operating system interfaces based on the UNIX operating system. The need for
standardization arose because enterprises using computers wanted to be able to develop programs that could
be moved among different manufacturer's computer systems without having to be recoded.
Private Branch Exchange (PBX)
A small to medium sized telephone system and switch that provides communications between onsite
telephones and exterior communications networks.
Programmable Read-Only Memory (PROM)
A memory chip where data is written only once as it remains there forever. Unlike RAM, PROMs retain their
contents when the computer is turned off.
Protocol
A formal set of rules developed by international standards bodies, LAN equipment vendors, or groups
governing the format, control, and timing of network communications. A set of conventions dealing with
transmissions between two systems. Typically defines how to implement a group of services in one or two
layers of the OSI reference model. Protocols can describe low-level details of machine-to-machine interfaces
or high-level exchanges between allocation programs.
Proxy Server
An intermediary program that acts as both a server and a client for the purpose of making requests on behalf
of other clients. Requests are serviced internally or by passing them on, possibly after translation, to other
servers. A proxy interprets, and, if necessary, rewrites a request message before forwarding it.
Public Switched Telephone Network (PSTN)
The local telephone company network that carries voice data over analog telephone lines.
Quality of Service (QoS)
Measure of the telephone service quality provided to a subscriber. This could be, for example, the longest time
someone should wait after picking up the handset before they receive dial tone (three seconds in most U.S.
states).
Real Time Control Protocol (RTCP)
RTCP is the control protocol designed to work in conjunction with RTP. It is standardized in RFC 1889 and
1890. In an RTP session, participants periodically send RTCP packets to convey feedback on quality of data
delivery and information of membership.
Realtime Transport Protocol (RTP)
An IETF standard for streaming realtime multimedia over IP in packets. Supports transport of real-time data
like interactive voice and video over packet switched networks.
Registrar Server
A server that accepts REGISTER requests. A registrar is typically co-located with a proxy or redirect server
and MAY offer location services.