Packet

A data element transmitted over a packet-switching network such as the Internet. A packet includes not just data but also address information about its origination and destination.

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Packet switching

A method of switching data in a network where individual packets of a set size and format are accepted by the network and delivered to their destinations. The sequence of the packets is maintained and the destination established by the exchange of control information (also contained in the packets) between the sending terminal and the network before the transmission starts. The network is open to all users, all the time, with packets from the various nodes being interleaved throughout the network. The packets can be sent in any order, as the control information sent at the beginning of the transmission ensures they are interpreted in the correct order at the receiving end. Because each packet carries its own control instructions, it can use any route to reach its destination.

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PACS

Personal Access Communication system; a digital cordless technology developed initially by Bell Labs in the US, PACS was designed to compete with DECT.

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PA-Managerr

CellGlide GPRS Priority Access Managerr. This component of the CellGlide GPRS Mobile Traffic Shaperr enables operators to leverage existing network infrastructure to generate instant revenue streams from priority access applications such as point-of-sale solutions, command and control push-to-talk, real-time data feeds, wireless back-up lines, and more.

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PAMR

Public Access Mobile Radio; Commercial service using trunking techniques in which multiple groups of users can set up their own closed systems within a shared public network.

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PAP

Public Access Profile; a DECT term.

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PCH

Paging channel; downlink only, the MS is informed of incoming calls by the BTS via the PCH.

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PCN

Personal communications Network; a designation initially used in the UK to refer to networks operating in the 1800MHz band (see also DCS1800). No longer in use.

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PCS 1900

Personal communication systems 1900MHz; the terminology used in the US to describe the new digital networks being deployed in the 1900MHz band; rarely used today.

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PCU

Packet Control Unit; an element in a GPRS/UMTS network.

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PDA

Personal Data Appliance/Assistant. Also known as Personal Digital Appliance.

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PDC

Personal Digital Communications; a digital cellular technology developed and deployed uniquely in Japan. A TDMA technology, PDC is incompatible with any other digital cellular standard.

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PDP

Packet Data Protocol.

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PDU

Protocol Data Unit.

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PEDC

Pan European Digital Communications; A designation occasionally used in the early 1990s to describe GSM. No longer in use.

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PHS/PHP

Personal Handy Phone system;Phone; a digital cordless technology developed in Japan which achieved great success. Deployed by NTT CoCoMo and other Japanese operations, PHS offered two-way communications, data services and Internet access and eventually won some 28 million customers. Now in decline as cellular's wide area capabilities offer better service.

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Piv6

The next generation of IP addressing designed to replace the current system Ipv4 which uses a 32 bit address code that limits the number of possible addresses. Ipv6 uses a 128 bit code ensuring that the possible number of IP addresses will be virtually limitless.

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PLMN

Public Land Mobile Network; any cellular operator's network.

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PMR

Private Mobile Radiocommunications; two-way radio technology widely used for dispatch and delivery services, taxi companies and the like. See TETRA.

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Point-of-Sale

A point-of-sale (POS) terminal is a computerized replacement for a cash register. Much more complex than the cash registers of even just a few years ago, the POS system can include the ability to record and track customer orders, process credit and debit cards, connect to other systems in a network, and manage inventory. Increasingly, POS terminals are also Web-enabled and/or operated over mobile devises, which makes remote training and operation possible, as well as inventory tracking across geographically-dispersed locations.

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PoP

Points of Presence; a method of measuring the value of a cellular license; the approximate number of potential customers within a geographical area.

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POTS

Plain Old Telephone Service.

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PSDN

Public Switched Data Network.

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PSPDN

Public Switched Packet Data Network.

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PSRCP

Public Safety Radio Communications Project; an initiative by the UK Government to standardize all emergency services communications on to a single digital technology (See TETRA).

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PSTN

Public Switched Telephone Network.

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PSU

Power supply Unit.

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PTO

Public Telecommunication Operator.

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PTT

Posts, Telephone and Telegraph Administration.

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Push-to-talk

In telephone or two-way radio systems, that method of communication over a speech circuit in which the talker is required to keep a switch operated while talking. Note: In two-way radio, push-to-talk operation must be used when the same frequency is employed by both transmitters. For use in noisy environments, or for privacy, some telephone handsets have push-to-talk switches that allow the speaker to be heard only when the switch is activated. Push-To-Talk service is based on the streaming of voice over GPRS, and is very bandwidth demanding and senstive to dalys in service. By providing real-time GPRS service differentiation and service admission control mechanisms, the CellGlide GPRS Mobile Traffic Shaperr minimizes investments in GPRS capacity required to support the successful introduction of high-quality PTT services.

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PWT

Personal Wireless Telecommunications; a variant of DECT developed for use in the USA.

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