PABX - Private Automatic Branch ExchangeIn portuguese, Posto Privado de Comutação Automática (PPCA). Private switching system, which ensures the input/output traffic of a set of extensions, as well as their internal interconnection. Small private switchboard for the interconnection of telephones, usually of a determined enclosed space or building.
PacketFinite group of bits which can be transmitted through a packet switching communications network. It consists of a sequence of binary digits, in accordance with a specific format, which includes the data to transfer and data on the signalisation of the connection.
Packet SwitchingSwitching technique in which communication between extremities is provided through the transmission of blocks of data (packets), whereby the channel is only occupied during the sending of this data, freeing up spare space for other data.
PagingSystem of radio messaging made up of sounds signals or characters and which uses small devices as reception terminals (commonly known as pagers).
PAL - Phase Alternating LineStandard used in Europe for the transmission of television, characterised by 625 lines and 25 images per second.
Parabolic AntennaType of antenna with a reflector in the shape of a parabola (''dish'') used for the emission and reception of satellite signals.
Parallel TransmissionMethod of transmission in which bits relative to the information to send are transmitted in successive groups, transmitted simultaneously by the channel. For this reason the amount of channels required is the same as the number of bits of each group.
PasswordAn access code to a determined functionality or facility. Used in IT to allow access to authorised users only. Generally is a made up of a set of characters and is the equivalent of a physical key.
Pay Per View (PPV)Term used in television for the service of acquisition of events on request (such as a football game or a film), as opposed to subscribing to a complete channel or package of channels. Generally it is used by television operators to make determined premium quality programmes available. Some pay-per-view systems require the customer to call a customer management centre requesting to see the event, others allow the users to buy the right to view the event through an on-screen menu and remote control, thereby receiving immediate authorisation.
Pay TVTelevision services (generally a channel or set of channels) paid for by the user, by means of subscription or other ways of service payment.
PCS - Personal Communications ServicesPCS, being an alternative to cellular communication, functions through cellular technology in that it sends calls from transmitter to transmitter - even if the individual making the call moves. PCS uses its own network; it is not a cellular network and offers fewer areas without signal. PCS transmitters are generally closer than their cellular equivalents.
Peer-to-peerExchange of data between equal levels of the OSI model. This term is also used to describe networks in which there is no client-server concept.
Peripheral EquipmentEquipment which works in conjunction with a computer or telecommunications system, but which is not an essential part of it, such as a printer or video terminal.
Personal Communications Services (PCS)PCS, being an alternative to cellular communication, functions through cellular technology in that it sends calls from transmitter to transmitter - even if the individual making the call moves. PCS uses its own network; it is not a cellular network and offers fewer areas without signal. PCS transmitters are generally closer than their cellular equivalents.
Personal Mobile Communication Network Operator via SatelliteEntities which are supported by a personal mobile communications systems operator via satellite and to which frequencies are allocated to provide transmission capacity for the supply of personal mobile communications via satellite services. These services may or may not involve the operation of fixed earth stations in national territory for interconnection to public telecommunications systems (gateway).
Phase Alternating Line (PAL)Standard used in Europe for the transmission of television, characterised by 625 lines and 25 images per second.
PIN - Personal Identification NumberUsed to restrict access to determined electronic communication services to their individual user. Works like an access code to a service which should only be known to the user.
PixelThe smallest partition (area) of an image, able to be shown and transmitted through a system and presented on a monitor. Represents the smallest unit of image that each computer or television set can manipulate.
Plenipotentiary Conference (PP)Plenipotentiary Conference of the International Telecommunication Union (ITU).
Point to PointTerm used to describe a connection/communication between two points. May also be used to describe a network in which the extremities communicate directly with each other.
Point-to-Point Protocol (PPP)Protocol which enables a computer to use a telephone line and a modem using TCP/IP.
POP - Point Of PresencePlace in which the Internet access supplier has equipment to provide his clients with access to the same, namely through telephone lines.
Port Operations ServiceIn portuguese, Serviço de Operações Portuárias (OP). Maritime Mobile Service in or near a port, between coast stations and ship stations, or between ship stations, in which messages are restricted to those relating to the operational handling, the movement and the safety of ships and, in emergency cases, to the safety of people. This service excludes messages which are of the nature of public correspondence.
PortabilityFeature which means that subscribers to publically available telephone services can request to maintain their number, in respect of the same service, irrespective of the company offering the service, in the case of geographic numbers, at a determined location, and in the case of other numbers, through national territory (operator portability).
Portable Audio ConnectionTransmitter placed on clothing used with one or more microphones, with greater autonomy of feed than microphone transmitters.
Portable Video ConnectionPortable camera in which the kit formed by the transmitter, feed and antenna are separate.
PortalType of Internet site. It functions like an entry door to other sites, making various services and a search mechanism available. It has diverse information, games, online shopping, and allows navigation to other addresses through the available directories.
Postal ItemPostal item shall mean an item addressed in the final form, which observes the physical and technical specifications that allows it to be sorted by a postal network as well as delivered at the address indicated on the object itself or on its wrapping, namely: a) An item of correspondence, which consists on a communication in written form on any kind of physical medium, including direct mail; b) Books, catalogues, newspapers and other periodicals; c) A postal parcel, which is a package containing merchandise or objects with or without commercial value.
Postal servicesMeans services consisting of the clearance, sorting, routing and delivery of postal items.
PP - Plenipotentiary ConferencePlenipotentiary Conference of the International Telecommunication Union (ITU).
PPP - Point-to-Point ProtocolProtocol which enables a computer to use a telephone line and a modem using TCP/IP.
PPV - Pay Per ViewTerm used in television for the service of acquisition of events on request (such as a football game or a film), as opposed to subscribing to a complete channel or package of channels. Generally it is used by television operators to make determined premium quality programmes available. Some pay-per-view systems require the customer to call a customer management centre requesting to see the event, others allow the users to buy the right to view the event through an on-screen menu and remote control, thereby receiving immediate authorisation.
PrefixCode consisting of one or more digits which allows the selection of different types of number formats, networks or services.
Premium ProgrammeProgramme considered to be of above average quality due to its exceptional character (such as a live sporting event), timing (such as the premiere of a film), or for other reasons, and for which the user is willing to pay an additional charge in order to see it. As a result, this type of programme is generally provided on premium channels or even using the pay-per-view system.
Pre-selectionIndirect access modality that requires a pre-designation of a company, which means that all comprised calls will be automatically forwarded through this company without the company's identification code having to be dialled.
Price TableDeclaration of a communications company which establishes the services provided, prices, terms and conditions of usage of these services.
Primary AccessAccess to ISDN in which 30 64 Kbit/s channels are available for voice or data and one at 64 Kbps for signalisation, providing a global speed of 2Mbit/s.
Private Automatic Branch Exchange (PABX)In portuguese, Posto Privado de Comutação Automática (PPCA). Private switching system, which ensures the input/output traffic of a set of extensions, as well as their internal interconnection. Small private switchboard for the interconnection of telephones, usually of a determined enclosed space or building.
Private InstallationTelecommunications installation for the exclusive use of the subscriber, without connection to the switching equipment of the telephone exchange.
Private KeyOne of a pair of asymmetrical keys known only by their owner, who can use it to place a digital signature on an electronic document, or decipher an electronic document previously enciphered with the corresponding public key.
Privileged Access ZoneIn portuguese, Zona de Acesso Privilegiado (ZAP). Place situated inside an autonomous residential fraction which is characterised by two close proaxial sockets, allowing the connection of two distinct signals to the same terminal device, coming from the coaxial networks.
Project ConsultantPerson or party registered with the regulatory body (ANACOM) as qualified to carry out projects involving the installation of or alterations to the telecommunications infrastructure.
Protected ServiceTelevision, radio broadcast or information society service, which is provided after remuneration and based on conditional access, or the supply of conditional access to the aforementioned services which is considered as a service in itself. An example of protected service is the premium television channels of the cable television distribution operators, access to which is restricted to those who subscribe to the service.
Provisional InstallationTemporary telecommunications installation for use when permanent installation is not justifiable or possible.
ProxyIntermediary application between computers allowing the communication between applications for computers which are not directly connected. The integration of a cache in a proxy allows the transfer speed to be increased, in the case of subsequent access to the same information after the first consultation.
Public Distribution NetworkSet of cables serving various subscribers which establishes the connection between the subscriber's equipment of the switchboard or equivalent and the distribution point (normally the main distribution frame of the subscriber's building or private block).
Public KeyOne of a pair of asymmetrical keys which is divulged and which is used to verify the authenticity of the owner of an electronic document or which can be used to encipher an electronic document for transmission to the owner of the same pair of keys.
Public Pay-TelephoneTerminal equipment to access the FTS, installed in public places, including conditional access, available to the general public, in the regime of a commercial offer.
Public Radioelectric DomainThe space through which the radioelectric waves can be propagated makes up the public radioelectric domain, whose management, administration and inspection are the responsibility of the State, under the terms of the law.
Public Telecommunications Network OperatorCompany licensed for the establishment or supply of a public telecommunications network, including the offer of leased circuits.