byte of overhead information used for path management. The entire frame is padded with either 13 or 14 nibbles of trailer to bring the transmission up to the exact bit rate used.

DS3 was intended to accommodate clock slips so PLCP frames have to be padded with variable amounts to accommodate the extra “stuff” bits DS3 needs inserted for this clock slip feature. The C1 overhead byte indicates the length of the padding.

The payload and the overhead functions are checked by a Bit Interleaved Parity (BIP) function to measure errors and performance degradation. This performance information is transmitted in the overhead.

Physical Medium Dependent (PMD)

This sublayer of the physical layer is concerned with bit timing, line coding and electrical or optical transmission functions.

PL-OAM

Physical Layer Operations and Maintenance

PLCP BIP

Physical Layer Convergence Protocol Bit Interleaved Parity

PLCP FEBE

Physical Layer Convergence Protocol Far End Block Error

PRBS Errors

Errors in a selected PRBS pattern.

Private MIB

A proprietary MIB that has variables which are used for probe configuration and control options.

Probe

A device on the LAN that monitors all frames and produces network management information including current and historical traffic statistics and snapshots of selected frames. Probes are also known as monitors.

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Agilent Technologies J3919A, J3972A manual Pl-Oam, Plcp BIP, Plcp Febe