PA
Pocket Adapter.
PABX
Private Automatic Branch eXchange. See PBX.
Packet loss
The losses of data in a packet based network, usually due to congestion and consequent buffer overflow.
Packet switched
A data communications network where information is divided into packets and delivered to their destination separately and possibly via different paths.
PAL
Phase Alternating Line system. The format for video transmission most widely adoptedin 50 Hz mains based countries.
PAT
Port address translation. This is a router option that is used to enable a local server to communicate internally or externally without revealing its own private IP address. All outbound packets have their IP address translated to the router's external IP address. Inbound packet addresses are translated by the router to the private IP address of the original server. PAT is configured by assigning a mapping between the private IP address of the host and the relevant TCP port (or socket) number. Many DSL services support static PAT, whereby a one-to-one mapping between a private and public address is configured on the router provided at the customer premises. PAT is commonly used in conjunction with Network Address Translation (NAT) to enable support for a local SMTP mail server on a DSL connection, via a preconfigured router mapping between port 25 (TCP socket assigned to mail service) and the single public IP address of the router. Customers contemplating PAT should remember that the address mappings are static and can only be accessed by their ISP and allow one mapping per service only. For this reason, Microcare would normally recommend a solution based on a combination of Real IP addresses and a managed firewall solution, rather than NAT/PAT, for the optimum combination of security, convenience and affordability.
Parallel port
A socket at the back of your computer that you typically use to connect a printer. You'll also need a password if you want to enter Intranets or specialist websites that prevent Internet users in general from viewing their contents emails service. You'll also need a password if you want to enter Intranets or specialist websites that prevent Internet users in general from viewing their contents
PBX
Private Branch eXchange. A private telephone switching system that allows telephone extensions to connect to each other as well as the outside world.
PC
Personal Computer.
PC interface
Allows you to connect your fax machine directly to a PC. With additional software (purchased separately), you can receive and send faxes, print and scan directly onto a PC.
PCI
Peripheral Component Interconnect. A peripheral bus technology that is commonly used in desktop computers.
PCM
Pulse Code Modulation. A widely used method of converting analogue telephony signals into digital form.
PDA
Personal Digital Assistant. Small handheld computer that acts as a personal organiser.
PDU
Protocol Data Unit. A frame of data transmitted over the physical layer of a network.
PER
Packed Encoding Rules. Describes how the values defined in ASN.1 should be encoded for transmission over a network. See also X.691.
PIP
Picture-In-Picture display also known as a self view. Used commonly in videoconferencing to allow preview of the transmitted image. Superimposed over received image.
Plug and Play
It means that you can connect it straight to your computer without having to waste time making any adjustments. Sound cards, modems and printers can all be Plug and Play devices
POP
Picture-Out of-Picture. As PIP but not superimposed over received image.
PoP
Point of Presence. A local telephone number through which you access your Internet Service Provider (ISP). The BT Internet ISP has PoPs all over the country
POP3
Post Office Protocol 3. Mail server protocol commonly used on the internet.
POTS
Plain Old Telephone System. See PSTN.
PPP
Point-to-point protocol. PPP is the Internet standard for serial comminications. Newer and better than its predecessor, SLIP, PPP defines how your modem connection exchanges data packets with other systems on the Internet.
Predictive dialling
A third party CTI application, predictive dialling removes all dialling responsibilities an agent. Once a call has been completed, the software automatically dials the next number or the agent calling list.
PRI
ISDN Primary Rate Interface. Consists of twenty-three ‘B’ (data) channels and one ‘D’ (signalling) channel of 64 kbits/s and 16 kbits/s respectively.
Print engine
The type of engine technology. Used (ie, thermal, thermal transfer, inkjet, LED and laser).
Protocol
The type of engine technology. Used (ie, thermal, thermal transfer, inkjet, LED and laser).
PSDN
Packet Switched Digital Network.
PSNR
Peak Signal to Noise Ratio. See also SNR.
PSTN
Public Switched Telephone Network. The conventional worldwide voice telephone network.
PTP
Point-to-point Tunneling Protocol. PPTP is a protocol developed by a number of companies, including Microsoft, that allows secure transmission of data in TCP/IP packets. PPTP and similar protocols are used to carry secure communications over Virtual Private Networksd that use public phone lines.
PVA
Personal Video Assistant.
