P
P-type Silicon
Silicon doped with an element containing one fewer electron in its outer layer, like phosphorous. When combined with silicon, phosphorous takes an electron from the outer ring of the silicon, leaving an electron hole which enables electric current to flow. for more info
PAL
Phase Alternate Line, a video format used in most parts of the world.
PAP
Password Authentication Protocol. An authentication protocol that allows Point-to-Point Protocol peers to authenticate one another.
PAP
Password Authentication Protocol. A security protocol that uses password protection to allow access to a network or host.
PBX
See Private Branch Exchange.
PCM
Pulse Coded Modulation
PCMCIA
Personal Computer Memory Card International Association. An international body and trade association that establishes standards for integrated circuit cards called PCMCIA cards - or PC cards. These are credit-card-sized devices that expand the capability of a portable computer or other device to include more memory, modems, or a portable disk drive.
PCS
Personal Communications Systems. A networking system which provides secure digital wireless communications in a high frequency range, around 1900 megahertz. It uses small low-powered base stations, and lightweight and compact personal communicators.
PDU
Protocol Data Unit
PLL
Permanent Logical Link
PND
Present Next Digit
POP
1) Point of presence. The location of a switching dial-in facility, usually for a long-distance telecommunications provider or an Internet service provider. Also, a local telephone number through which you can access your ISP. 2) Post Office Protocol. An extensible protocol for retrieving email from a remote server.
POP (Point of Presence)
This is a point-of-presence of an Internet service provider, used to facilitate remote users' access to the range of applications and IP addresses in the internetwork.
POST
Power-On Self Test. A diagnostic test the Ascend unit performs when it first starts up or after a system reset. While the yellow FAULT LED on the front panel remains solidly lit, the Ascend unit checks system memory, configuration, installed modules, and the T11 connections. If the Ascend unit fails any of these tests, the AFAULT (or CON) LED remains lit or blinks.
PPP
Point-to-Point Protocol. Provides a standard means of encapsulating data packets sent over a single-channel WAN link. It is the standard WAN encapsulation protocol for the interoperability of bridges and routers. PPP is also supported in workstations, allowing direct dial-up access from a personal computer to a corporate LAN or ISP. Using PPP ensures basic compatibility with non-Ascend devices. Both the dialing side and the answering side of the link must support PPP.
PPTP Access Concentrator (PAC)
A PAC receives incoming PPP calls and initiates a connection to the PPTP Network Server (PNS).
PRI, ISDN PRI
See Primary Rate Interface.
PRM
Packet Radio Measurement
PSDN
Packet-Switched Data Network. In a packet-switched network, no connection is required end-to-end. It is generally more efficient for data transfers and better for redundancy (where other circuits are automatically available if a line goes down).
PVC
Protocol Version Control
PVP
Packet Video Protocol
Package
In chip manufacture, the protective container of an electronic component or chip. It includes the external terminals that provide electrical access to the components inside. for more info.
Packet
A block of information sometimes called a cell, frame, data unit, server unit, or signaling unit. Although each of these elements does have unique attributes, in essence, all are packets.
Packet Assembler Disassembler (PAD)
A term used with the X.25 network that refers to a terminal multiplexer device that forms a connection between the terminals and hosts across an X.25 network. A PAD accepts characters from a conventional terminal and sends them across an X.25 network.
Packet Field
A portion of a packet that contains a specific kind of information. For example, the data field in a packet contains the data being transmitted between applications. The header field can contain information identifying the packet type and any error-checking mechanisms.
Packet Filter
The ability to search a packet to determine destination and then route the packet or block it. Packet filters help control network traffic.
Packet Switching
A technology for sending data over a network - the Internet, for example. The data that emerges from a connected device is broken into chunks called packets. Each packet contains the address of its origin (source) and the address of its destination. Data packets from many different sources can travel along the same lines and be sorted and directed through different routes by routers along the way. When all the packets forming a message arrive at the destination, they are recompiled into the original message.
Packet-Level Inverse Multiplexing
A method of inverse multiplexing in which the inverse mux performs its function at the packet level using the MP or MPP protocol. One data packet goes over the first circuit, the next goes over the second circuit, and so on, until all the data packets are distributed over all the available circuits. The receiving end adjusts for network-induced delay and reassembles the data packets into their proper order. This inverse multiplexing technique is also referred to as load balancing. Telecommuting applications use packet-level inverse multiplexing.
Packet-switched Network
A network that consists of a series of interconnected circuits on which data packets can travel by one of several routes.
Packet-switched Public Data Network (PSPDN)
A PSPDN is an X.25 network.
Parameters
The record in a central office database that specifies equipment, software, options, and the addresses of peripheral equipment used in call processing.
Parity
In 7-bit communication, each device sends only the first 128 characters in the ASCII character set, because each of these characters can be represented by seven bits or fewer. Parity is a way for a device to determine whether it has received data exactly as the sending device transmitted it. Each device must determine whether it will use even parity, odd parity, or no parity.
Parity Check
A process for checking the integrity of a character. A parity check appends a bit to a character or word to make the total number of binary 1 digits in the character or word (excluding the parity bit) either odd (for odd parity) or even (for even parity).
Passive Optical Network
A Fiber in the Loop architecture that splits the optical signal traveling toward the customer and partitions it among several customers.
Password
A word or character string recognized by automatic means that permits a user access to protected storage, files, or input or output devices.
Password Prompt
The prompt that the terminal server displays when asking the user for his or her password.
Peer
In data networking, a router that operates on the same protocol layer as another router.
Perl
Practical Extraction Report Language. A programming language that combines syntax from the UNIX operating system. Perl is designed to handle a variety of system administrator functions. Perl is used on Web servers.
Permanent Virtual Circuit
A logical link established in a packet network that assures a connection and bandwidth for subscribers without actually having to dedicate physical facilities.
Personal Communications Network
A digital, wireless telephone concept, similar to cellular network, in which smaller low-power cells are used in conjunction with small personal handsets to transmit within small geographic areas.
Personal Communications Number (PCN)
Personal Communications Number: in PCS, a telephone number, which is permanently assigned to a subscriber regardless of the person's location or service provider. The PCN remains static even if the user changes handsets.
Personal Communications Systems (PCS)
Personal Communications Systems: a networking system which provides secure digital wireless communications in a high frequency range, around 1900 megahertz. It uses small low-powered base stations, light and compact personal communicators, PCS Mobile Switching Centers (MSC), Intelligent Network (IN), and Signaling System 7 (SS7). It offers voice and data transmission capabilities, enhanced mobile connection, and heightened subscriber capacity as well as features, like caller ID and alphanumeric messaging.
Personal Communicator
A lightweight, portable handset used to transmit and receive voice and data information in a PCS network
Phase Alternating Line (PAL)
European TV standard that uses 625-line resolution 50 half frames per second used in most of Western Europe, Australia, parts of Africa and the Middle East, and parts of Latin America. See National Television Standards Committee.
Phase Modulation (PM)
A scheme in which the message signal merges with the carrier so that the carrier's phase is varied.
Phase Shift Keying
A form of modulation in which digital information is conveyed by changing the phase of the signal.
Phone #, Dial #
The preferred term is dial #.
Photodetector
In a lightwave system, a device that turns pulses of light into bursts of electricity.
Photodiode
Light detector in a fiber optic signal transport system that generates an electric current in proportion to the intensity of the light falling on it.
Photodiode current monitor
A device that converts electrical current to a DC voltage, for the monitoring of the optical power. This conversion is typically a 1:1.
Photolithography
In semiconductor technology, a way of creating a circuit pattern on a chip by exposing areas covered by a sensitive film to light. The light-sensitive film is known as a photoresist or resist. for more info.
Photon
The fundamental unit of light and other forms of electromagnetic energy. Photons are to optical fibers what electrons are to copper wires.
Photonics
In communication technology, the use of fundamental particles of light, called photons, to form coded light pulses that convey information in digital form.
Photophone
One of Alexander Graham Bell's many bright ideas. The device used sunlight, reflected by mirrors, to transmit conversations. It worked fine, but only in good weather and daylight.
Photoresist (Resist)
In chip circuit design, light-sensitive material that is applied as a thin film on the surface of a wafer. Used for transferring the image of the circuit pattern to the wafer's surface. for more info
Pigtail
A short piece of un-connectorized optical fiber connected to either the transmitter or receiver. This pigtail intern would be spliced to the transmission fiber.
Ping
This is the command invoked on many systems to send ICMP echo requests. Ping has several versions. The most sophisticated Pings send a series of ICMP echo requests, capture responses, and corollary statistics regarding data packet loss. The user can determine the length of the ICMP request and designate an interval between tries.
Pipeline
The name of an Ascend product family of network access equipment with integrated remote LAN access capabilities. Pipeline allows remotely located branch offices, telecommuters, or traveling computer users to access corporate backbone LAN resources.
Plain Old Telephone Service (POTS)
The analog dial-tone-type telephone networks and services in place worldwide, with transmission rates up to 52Kbps. In contrast, telephone services based on digital communications lines, such as ISDN, have higher speeds and bandwidths. The POTS networks also called the public switched telephone network.
Plasma Etching
A process that creates microscopic electrical paths and insulating barriers in integrated circuits. The process literally carves channels through multiple layers of the chip.
Point to Point link
See Point-to-Point protocol (PPP).
Point-to-Point Protocol (PPP)
in data communications, a protocol that provides connections between routers and between hosts and the network over synchronous and asynchronous circuits.
Polarization
1) A technique used in satellite communications to increase the capacity of the satellite transmission channels by reusing the satellite transponder frequencies. 2) The direction of the electric field in the lightwave.
Port
The physical channel or connection through which data flows in and out of a device, such as a computer.
Port Speed
The rate at which data is accepted by the port at the end of the wire.
Portal Site
A website, like Yahoo or Netscape, that helps users find their way around the web.
Post, Telephone and Telegraph
The common name given to government agencies that provide communications services in those nations where communications utilities are owned by the government.
Primary Rate Interface
An ISDN subscriber line, consisting of twenty-three 64 kbit/s B channels in North America (thirty 64 kbit/s channels elsewhere) and one 64 kbit/s D channel, used for signaling purposes.
Primary Rate Interface (PRI)
The ISDN standards that bundle multiple circuits over a single link. In the US, it consists of 24 circuit switched B (bearer) channels plus one packet-switched D (data) channel. It is the ISDN equivalent of a T1 circuit (1.544 Mbps).
Private Branch Exchange (PBX)
A private switching system, usually serving an organization, such as a business or a government agency, and usually located on the customer's premises.
Private Network
A network, usually operated by a single corporate entity, made up of dedicated lines leased from the carriers, and switching equipment located on the corporate premises.
Processor
Sometimes called the CPU, or central processing unit. Hardware that performs a systematic sequence of operations under the control of software programs.
Promiscuous Mode
A Bridging parameter mode that determines that the Ethernet controller in the Ascend unit accepts all packets and passes them up the protocol stack for a higher-level decision on whether to route, bridge, or reject them. This mode is appropriate if you are using the Ascend unit as a bridge.
Prompts
1. In telephony, recorded instructions delivered to a user by voice processing units. Prompts may include menus or other information that is played each time the user enters the system. 2. In computing, messages from a program instructing a user on how to use the system.
Protocol
A set of rules governing message exchange over a network or internetwork. Examples of commonly used protocols are TCP/IP (Transmission Control Protocol/Internet Protocol), PPP (Point-to-Point Protocol), and IPX (Internet Packet Exchange).
Protocol Stack
The hierarchy of protocols used in a communications network. Network architectures designed in layers are referred to as stacks. See OSI.
Provisioning
The process by which a service provider, such as a telephone company, sets up the circuits necessary to provide a telecommunications service for a customer. Service carriers do so by programming their switches to provide the service.
Proxy ARP
If the Pipeline is the default router on a network, then packets destined for any of the hosts on the network are sent to the Pipeline. If any of these hosts needs to respond to an ARP request (a request to provide its physical address so that a connection can be established), and the host is not on the local network (ARP requests are only broadcast on a local network), the Pipeline can respond on behalf of the remote host to establish the connection. This is possible when the Pipeline is set to function in Proxy Mode.
Proxy Mode
A remote host can be assigned an IP address on the local network through its Connection profile on the Pipeline. Local hosts on the network see the remote host as if it were on the local network. When calls are made to the remote host, the Pipeline acts on behalf of the remote host and replies to requests and forwards packets. Proxy mode is enabled on the Pipeline via the Protocols section of the configuration software.
Proxy Server
Also called a proxy, a network application that acts as a firewall by breaking the network connection between the sender and receiver. All input is shunted out a different port, closing a straight path between two networks and preventing a hacker from obtaining internal addresses and details about a private network.
Public Network
A network operated by the carriers (IECs and LECs) which includes network-based services and network-based switching.
Public Switched Telephone Network (PSTN)
The worldwide telephone network.
Pulse Code Modulation
Technique for digitizing speech that samples sound waves 8,000 times a second and converts each sample into an 8-bit binary number resulting in a 64.000 bit-per-second signal, the size of a traditional voice channel.
Px64
Common reference to the CCITT standards (H.261 et. al.) which describe methods to allow for videoconferencing system interoperability. RADIUS
parallel port
A socket on a computer used to connect a printer or other peripheral device. It may also be used to attach a portable hard disk, tape backup or CD-ROM.
Silicon doped with an element containing one fewer electron in its outer layer, like phosphorous. When combined with silicon, phosphorous takes an electron from the outer ring of the silicon, leaving an electron hole which enables electric current to flow. for more info
PAL
Phase Alternate Line, a video format used in most parts of the world.
PAP
Password Authentication Protocol. An authentication protocol that allows Point-to-Point Protocol peers to authenticate one another.
PAP
Password Authentication Protocol. A security protocol that uses password protection to allow access to a network or host.
PBX
See Private Branch Exchange.
PCM
Pulse Coded Modulation
PCMCIA
Personal Computer Memory Card International Association. An international body and trade association that establishes standards for integrated circuit cards called PCMCIA cards - or PC cards. These are credit-card-sized devices that expand the capability of a portable computer or other device to include more memory, modems, or a portable disk drive.
PCS
Personal Communications Systems. A networking system which provides secure digital wireless communications in a high frequency range, around 1900 megahertz. It uses small low-powered base stations, and lightweight and compact personal communicators.
PDU
Protocol Data Unit
PLL
Permanent Logical Link
PND
Present Next Digit
POP
1) Point of presence. The location of a switching dial-in facility, usually for a long-distance telecommunications provider or an Internet service provider. Also, a local telephone number through which you can access your ISP. 2) Post Office Protocol. An extensible protocol for retrieving email from a remote server.
POP (Point of Presence)
This is a point-of-presence of an Internet service provider, used to facilitate remote users' access to the range of applications and IP addresses in the internetwork.
POST
Power-On Self Test. A diagnostic test the Ascend unit performs when it first starts up or after a system reset. While the yellow FAULT LED on the front panel remains solidly lit, the Ascend unit checks system memory, configuration, installed modules, and the T11 connections. If the Ascend unit fails any of these tests, the AFAULT (or CON) LED remains lit or blinks.
PPP
Point-to-Point Protocol. Provides a standard means of encapsulating data packets sent over a single-channel WAN link. It is the standard WAN encapsulation protocol for the interoperability of bridges and routers. PPP is also supported in workstations, allowing direct dial-up access from a personal computer to a corporate LAN or ISP. Using PPP ensures basic compatibility with non-Ascend devices. Both the dialing side and the answering side of the link must support PPP.
PPTP Access Concentrator (PAC)
A PAC receives incoming PPP calls and initiates a connection to the PPTP Network Server (PNS).
PRI, ISDN PRI
See Primary Rate Interface.
PRM
Packet Radio Measurement
PSDN
Packet-Switched Data Network. In a packet-switched network, no connection is required end-to-end. It is generally more efficient for data transfers and better for redundancy (where other circuits are automatically available if a line goes down).
PVC
Protocol Version Control
PVP
Packet Video Protocol
Package
In chip manufacture, the protective container of an electronic component or chip. It includes the external terminals that provide electrical access to the components inside. for more info.
Packet
A block of information sometimes called a cell, frame, data unit, server unit, or signaling unit. Although each of these elements does have unique attributes, in essence, all are packets.
Packet Assembler Disassembler (PAD)
A term used with the X.25 network that refers to a terminal multiplexer device that forms a connection between the terminals and hosts across an X.25 network. A PAD accepts characters from a conventional terminal and sends them across an X.25 network.
Packet Field
A portion of a packet that contains a specific kind of information. For example, the data field in a packet contains the data being transmitted between applications. The header field can contain information identifying the packet type and any error-checking mechanisms.
Packet Filter
The ability to search a packet to determine destination and then route the packet or block it. Packet filters help control network traffic.
Packet Switching
A technology for sending data over a network - the Internet, for example. The data that emerges from a connected device is broken into chunks called packets. Each packet contains the address of its origin (source) and the address of its destination. Data packets from many different sources can travel along the same lines and be sorted and directed through different routes by routers along the way. When all the packets forming a message arrive at the destination, they are recompiled into the original message.
Packet-Level Inverse Multiplexing
A method of inverse multiplexing in which the inverse mux performs its function at the packet level using the MP or MPP protocol. One data packet goes over the first circuit, the next goes over the second circuit, and so on, until all the data packets are distributed over all the available circuits. The receiving end adjusts for network-induced delay and reassembles the data packets into their proper order. This inverse multiplexing technique is also referred to as load balancing. Telecommuting applications use packet-level inverse multiplexing.
Packet-switched Network
A network that consists of a series of interconnected circuits on which data packets can travel by one of several routes.
Packet-switched Public Data Network (PSPDN)
A PSPDN is an X.25 network.
Parameters
The record in a central office database that specifies equipment, software, options, and the addresses of peripheral equipment used in call processing.
Parity
In 7-bit communication, each device sends only the first 128 characters in the ASCII character set, because each of these characters can be represented by seven bits or fewer. Parity is a way for a device to determine whether it has received data exactly as the sending device transmitted it. Each device must determine whether it will use even parity, odd parity, or no parity.
Parity Check
A process for checking the integrity of a character. A parity check appends a bit to a character or word to make the total number of binary 1 digits in the character or word (excluding the parity bit) either odd (for odd parity) or even (for even parity).
Passive Optical Network
A Fiber in the Loop architecture that splits the optical signal traveling toward the customer and partitions it among several customers.
Password
A word or character string recognized by automatic means that permits a user access to protected storage, files, or input or output devices.
Password Prompt
The prompt that the terminal server displays when asking the user for his or her password.
Peer
In data networking, a router that operates on the same protocol layer as another router.
Perl
Practical Extraction Report Language. A programming language that combines syntax from the UNIX operating system. Perl is designed to handle a variety of system administrator functions. Perl is used on Web servers.
Permanent Virtual Circuit
A logical link established in a packet network that assures a connection and bandwidth for subscribers without actually having to dedicate physical facilities.
Personal Communications Network
A digital, wireless telephone concept, similar to cellular network, in which smaller low-power cells are used in conjunction with small personal handsets to transmit within small geographic areas.
Personal Communications Number (PCN)
Personal Communications Number: in PCS, a telephone number, which is permanently assigned to a subscriber regardless of the person's location or service provider. The PCN remains static even if the user changes handsets.
Personal Communications Systems (PCS)
Personal Communications Systems: a networking system which provides secure digital wireless communications in a high frequency range, around 1900 megahertz. It uses small low-powered base stations, light and compact personal communicators, PCS Mobile Switching Centers (MSC), Intelligent Network (IN), and Signaling System 7 (SS7). It offers voice and data transmission capabilities, enhanced mobile connection, and heightened subscriber capacity as well as features, like caller ID and alphanumeric messaging.
Personal Communicator
A lightweight, portable handset used to transmit and receive voice and data information in a PCS network
Phase Alternating Line (PAL)
European TV standard that uses 625-line resolution 50 half frames per second used in most of Western Europe, Australia, parts of Africa and the Middle East, and parts of Latin America. See National Television Standards Committee.
Phase Modulation (PM)
A scheme in which the message signal merges with the carrier so that the carrier's phase is varied.
Phase Shift Keying
A form of modulation in which digital information is conveyed by changing the phase of the signal.
Phone #, Dial #
The preferred term is dial #.
Photodetector
In a lightwave system, a device that turns pulses of light into bursts of electricity.
Photodiode
Light detector in a fiber optic signal transport system that generates an electric current in proportion to the intensity of the light falling on it.
Photodiode current monitor
A device that converts electrical current to a DC voltage, for the monitoring of the optical power. This conversion is typically a 1:1.
Photolithography
In semiconductor technology, a way of creating a circuit pattern on a chip by exposing areas covered by a sensitive film to light. The light-sensitive film is known as a photoresist or resist. for more info.
Photon
The fundamental unit of light and other forms of electromagnetic energy. Photons are to optical fibers what electrons are to copper wires.
Photonics
In communication technology, the use of fundamental particles of light, called photons, to form coded light pulses that convey information in digital form.
Photophone
One of Alexander Graham Bell's many bright ideas. The device used sunlight, reflected by mirrors, to transmit conversations. It worked fine, but only in good weather and daylight.
Photoresist (Resist)
In chip circuit design, light-sensitive material that is applied as a thin film on the surface of a wafer. Used for transferring the image of the circuit pattern to the wafer's surface. for more info
Pigtail
A short piece of un-connectorized optical fiber connected to either the transmitter or receiver. This pigtail intern would be spliced to the transmission fiber.
Ping
This is the command invoked on many systems to send ICMP echo requests. Ping has several versions. The most sophisticated Pings send a series of ICMP echo requests, capture responses, and corollary statistics regarding data packet loss. The user can determine the length of the ICMP request and designate an interval between tries.
Pipeline
The name of an Ascend product family of network access equipment with integrated remote LAN access capabilities. Pipeline allows remotely located branch offices, telecommuters, or traveling computer users to access corporate backbone LAN resources.
Plain Old Telephone Service (POTS)
The analog dial-tone-type telephone networks and services in place worldwide, with transmission rates up to 52Kbps. In contrast, telephone services based on digital communications lines, such as ISDN, have higher speeds and bandwidths. The POTS networks also called the public switched telephone network.
Plasma Etching
A process that creates microscopic electrical paths and insulating barriers in integrated circuits. The process literally carves channels through multiple layers of the chip.
Point to Point link
See Point-to-Point protocol (PPP).
Point-to-Point Protocol (PPP)
in data communications, a protocol that provides connections between routers and between hosts and the network over synchronous and asynchronous circuits.
Polarization
1) A technique used in satellite communications to increase the capacity of the satellite transmission channels by reusing the satellite transponder frequencies. 2) The direction of the electric field in the lightwave.
Port
The physical channel or connection through which data flows in and out of a device, such as a computer.
Port Speed
The rate at which data is accepted by the port at the end of the wire.
Portal Site
A website, like Yahoo or Netscape, that helps users find their way around the web.
Post, Telephone and Telegraph
The common name given to government agencies that provide communications services in those nations where communications utilities are owned by the government.
Primary Rate Interface
An ISDN subscriber line, consisting of twenty-three 64 kbit/s B channels in North America (thirty 64 kbit/s channels elsewhere) and one 64 kbit/s D channel, used for signaling purposes.
Primary Rate Interface (PRI)
The ISDN standards that bundle multiple circuits over a single link. In the US, it consists of 24 circuit switched B (bearer) channels plus one packet-switched D (data) channel. It is the ISDN equivalent of a T1 circuit (1.544 Mbps).
Private Branch Exchange (PBX)
A private switching system, usually serving an organization, such as a business or a government agency, and usually located on the customer's premises.
Private Network
A network, usually operated by a single corporate entity, made up of dedicated lines leased from the carriers, and switching equipment located on the corporate premises.
Processor
Sometimes called the CPU, or central processing unit. Hardware that performs a systematic sequence of operations under the control of software programs.
Promiscuous Mode
A Bridging parameter mode that determines that the Ethernet controller in the Ascend unit accepts all packets and passes them up the protocol stack for a higher-level decision on whether to route, bridge, or reject them. This mode is appropriate if you are using the Ascend unit as a bridge.
Prompts
1. In telephony, recorded instructions delivered to a user by voice processing units. Prompts may include menus or other information that is played each time the user enters the system. 2. In computing, messages from a program instructing a user on how to use the system.
Protocol
A set of rules governing message exchange over a network or internetwork. Examples of commonly used protocols are TCP/IP (Transmission Control Protocol/Internet Protocol), PPP (Point-to-Point Protocol), and IPX (Internet Packet Exchange).
Protocol Stack
The hierarchy of protocols used in a communications network. Network architectures designed in layers are referred to as stacks. See OSI.
Provisioning
The process by which a service provider, such as a telephone company, sets up the circuits necessary to provide a telecommunications service for a customer. Service carriers do so by programming their switches to provide the service.
Proxy ARP
If the Pipeline is the default router on a network, then packets destined for any of the hosts on the network are sent to the Pipeline. If any of these hosts needs to respond to an ARP request (a request to provide its physical address so that a connection can be established), and the host is not on the local network (ARP requests are only broadcast on a local network), the Pipeline can respond on behalf of the remote host to establish the connection. This is possible when the Pipeline is set to function in Proxy Mode.
Proxy Mode
A remote host can be assigned an IP address on the local network through its Connection profile on the Pipeline. Local hosts on the network see the remote host as if it were on the local network. When calls are made to the remote host, the Pipeline acts on behalf of the remote host and replies to requests and forwards packets. Proxy mode is enabled on the Pipeline via the Protocols section of the configuration software.
Proxy Server
Also called a proxy, a network application that acts as a firewall by breaking the network connection between the sender and receiver. All input is shunted out a different port, closing a straight path between two networks and preventing a hacker from obtaining internal addresses and details about a private network.
Public Network
A network operated by the carriers (IECs and LECs) which includes network-based services and network-based switching.
Public Switched Telephone Network (PSTN)
The worldwide telephone network.
Pulse Code Modulation
Technique for digitizing speech that samples sound waves 8,000 times a second and converts each sample into an 8-bit binary number resulting in a 64.000 bit-per-second signal, the size of a traditional voice channel.
Px64
Common reference to the CCITT standards (H.261 et. al.) which describe methods to allow for videoconferencing system interoperability. RADIUS
parallel port
A socket on a computer used to connect a printer or other peripheral device. It may also be used to attach a portable hard disk, tape backup or CD-ROM.
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