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POP.
See Point of Presence.
POTS.
See Plain Old Telephone Service.
POTS Splitter.
A device that uses filters to separate voice from data signals when they are to be carried on
the same phone line, required for several types of DSL service.
Powerline Networking.
A type of local networking that uses existing power lines within the office.
PPPoA.
Point to Point Protocol over ATM. See Point to Point Protocol.
PPPoE.
Point to Point Protocol over Ethernet. See Point to Point Protocol.
Private Branch eXchange (PBX).
A private phone switching system used within a company that
connects telephones to each other, allowing users to make inter-office as well as outbound telephone calls.
Most companies now use a digital PBX switching system that utilize digital telephones, and includes
features such as voicemail, call management, and caller ID.
PRI-ISDN.
See Primary-rate ISDN.
Primary-rate ISDN (PRI-ISDN).
The primary rate ISDN interface provides 23-64 Kilobits per second
channels (called B channels) to carry voice or data and one 16 Kilobits per second signaling channel (the D
channel) for call information.
Public Switched Telephone Network (PSTN).
The worldwide communications network that carries
phone calls and data.
R
Radio Frequency (RF).
Electromagnetic carrier waves upon which audio, video, or data signals can be
superimposed for transmission.
RADSL.
See Rate-Adaptive Asymmetric Digital Subscriber Line.
Rate-adaptive Digital Subscriber Line (RADSL).
A variation of DSL that uses carrierless amplitude
phase modulation, divides the available frequencies into discrete sub-channels and also maximizes
performance by adjusting the transmission to the quality of the phone line while in use.
Residential Gateway.
A device that allows multiple devices access to the Internet through one single
high-speed Internet connection.
RF.
See Radio Frequency.
Request for Comment (RFC) 1483.
RFC 1483 was developed to allow the successful transmission of
multiple protocols over ATM networks. This RFC is broken down into two methods of implementation;
VC based multiplexing and LLC encapsulation. The breakdown on both are mentioned below.
RJ-45 Plug.
Short for Registered Jack-45, the RJ-45 is an eight-wire plug used to connect computers onto
a local area network (LAN), especially Ethernet.
Roaming.
Movement of a wireless node between two microcells.
Router.
The central switching device in a packet-switched computer network that directs and controls the
flow of data through the network.
