Alcatel-Lucent 1643 AMS - Introduction

Introduction
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Purpose of performance monitoring
The purpose of performance monitoring is:
1. to detect degraded performance of the transport functionality in order to support
pro-active maintenance activities, for example replacing equipment before the
impact of the performance degradation on service becomes unacceptable
(maintenance-oriented performance monitoring).
2. to collect performance data over a long period (typically months) in order to verify
the quality of the transport service (quality-of-service-oriented performance
monitoring).
Near-end and far-end performance monitoring
In principle, two kinds of performance monitoring can be distinguished:
• Near-end performance monitoring
Performance parameters are derived from bit errors and defects in the incoming
signal.
• Far-end performance monitoring
Performance parameters are derived from the remote information (REI/RDI) in the
incoming signal. The meaning of the remote information will be explained in more
detail afterwards in this chapter.
Performance monitoring of a bidirectional path
To monitor the performance of a bidirectional path, near-end and far-end performance
monitoring information is correlated. The bidirectional path is considered unavailable if
at least one of the directions is unavailable.
The following figure shows an example of a bidirectional path:
At NE A, the near-end information represents the performance of the unidirectional
trail from NE Z to NE A, while the far-end information represents the performance of
the unidirectional trail from NE A to NE Z.
At NE Z, the near-end information represents the performance of the unidirectional
trail from NE A to NE Z, while the far-end information represents the performance of
the unidirectional trail from NE Z to NE A.
NE A
TTP
NE B
CTP
NE I
CTP
NE Z
TTP
REI
RDI
REI
RDI
Performance monitoring
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10-4
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Issue 4, May 2007