Agilent Technologies J3972A - Manual (Page 173)

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Protocol
A set of rules that governs data transfer among devices on a network. A protocol
identifies the handshake type, frame size and format, timing, error recovery
scheme, word size or other characteristics of each transfer, depending on the
system.
Protocol Data Unit (PDU)
A segment of data generated by a specific layer of a protocol stack; usually
contains information from the next higher layer encapsulated with header and
trailer data generated by the later in question.
Pseudo-Random Bit Sequence (PRBS)
These are sequences of bits used for BERT testing. To simplify testing, certain
lengths are standardized to particular sequences. For high-speed ATM, the
standard supported lengths are 2^15, 2^20 and 2^23. The length is the number of
bits which will be transmitted before the sequence repeats.
Remote Alarm Indication (RAI)
The Remote Alarm Indication (RAI (Yellow)) is a 1-bit field in the Path Status
octet (G1) of a PLCP frame. An RAI value in a PLCP frame is set to 1 after an
error condition has been detected. The RAI is cleared (0) after the error condition
has not occurred for a certain period of time.
Ring
See Token-Ring.
RMON MIB (Remote Network Monitoring MIB)
The collection of objects defined by the Internet Engineering Task Force in RFC
1757, RFC 1213, RFC 1157, RFC 2021, RFC 2074, Token-Ring RMON
Extensions, and Agilent probe private MIB that are used for network monitoring.
RS-232 port
A serial interface connector on a computer or peripheral that adheres to the current
RS-232 standard. The probe’s RS-232 port adheres to this standard.
SAM (System Administration Manager)
A configuration tool provided by HP-UX for managing system resources and
changing configuration parameters.