VeEX VePAL TX300M, User Manual

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Evaluation According to ITU-T G.826
G.826 recommendation makes provision for higher bit rates and allows in-service measurement using the evaluation of block
errors.
The following are evaluated: ES, SES, BE, BBE, and UAS.
Pass/Fail result depends on path allocation of 0.1 to 100%.
In-Service Measurement (ISM):
Simultaneous in-service measurement of “near end” and “far-end” of a selected path.
Out-of-Service Measurement (OOS):
Out-of-service measurement using bit errors in a test pattern.
Definitions:
Errored Second (ES):
A one-second time interval containing one or more errored blocks.
Severely Errored Second (SES):
A one-second time interval in which more than 30% of the blocks are errored
Block Error (BE):
A block containing one or more errored bits.
Background Block Error (BBE):
An errored block that is not a SES.
Unavailable Second (UAS):
A circuit is considered to be unavailable from the first of at least ten consecutive SES. The
circuit is available from the first of at least ten consecutive seconds which are not SES.
Note:
The recommended measurement time for G.821 and G.826 is 30 days.
G.828 Performance Analysis
TX300S_e-manual_D07-00-064P_RevA00