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GLOSSARY
Proxy - the process in which one system acts for another system to answer protocol requests.
Proxy Agent - an agent that queries on behalf of the manager, used to monitor objects that are not directly manageable.
PSN (Packet Switched Network) - a network designed to carry data in the form of packets. The packet and its format is internal to that network.
PT (Payload Type) - bits 2...4 in the fourth byte of an ATM cell header. The PT indicates the type of information carried by the cell. At this time, values 0...3 are used to identify various types of user data, values 4 and 5 indicate man- agement information, and values 6 and 7 are reserved for future use.
PVC (Permanent Virtual Circuit (or Channel)) - a circuit or channel through an ATM network provisioned by a carrier between two endpoints; used for dedicated
Q.2931 - Derived from Q.93B, the narrowband ISDN signalling protocol, an ITU standard describing the signalling protocol to be used by switched vir- tual circuits on ATM LANs.
Relaying - a function of a layer by means of which a layer entity receives data from a corresponding entity and transmits it to another corresponding entity.
RFCs (Requests For Comment) - IETF documents suggesting protocols and policies of the Internet, inviting comments as to the quality and validity of those policies. These comments are collected and analyzed by the IETF in order to finalize Internet standards.
RFI (Radio Frequency Interference) - the unintentional transmission of radio signals. Computer equipment and wiring can both generate and receive RFI.
RIP (Routing Information Protocol) - a distance
RISC (Reduced Instruction Set Computer) - a generic name for CPUs that use a simpler instruction set than more traditional designs.
Router - a device that forwards traffic between networks or subnetworks based on network layer information.
SBus - hardware interface for
SAP (Service Access Point) - the point at which an entity of a layer provides services to its LM entity or to an entity of the next higher layer.