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GLOSSARY
OSI (Open Systems Interconnection) - the
OSPF (Open Shortest Path First) Protocol - a routing algorithm for IP that incorporates
Packet Switching - a communications paradigm in which packets (messages) are individually routed between hosts with no previously established com- munications path.
PBX (Private Branch Exchange) - a private phone system (switch) that con- nects to the public telephone network and offers
PCI (Peripheral Component Interconnect) - a
PCM (Pulse Code Modulation) - a modulation scheme that samples the information signals and transmits a series of coded pulses to represent the data.
PDN (Public Data Network) - a network designed primarily for data trans- mission and intended for sharing by many users from many organizations.
PDU (Protocol Data Unit) - a unit of data specified in a layer protocol and consisting of protocol control information and layer user data.
Peak Cell Rate - at the PHY Layer SAP of a
Peer Entities - entities within the same layer.
PHY (Physical Layer) - the actual cards, wires, and/or