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Cisco ONS 15454 DWDM Reference Manual, R8.5
78-18343-02
Chapter 17      Performance Monitoring
17.9    SDH PM Parameter Definitions
MS-ES Multiplex Section Errored Second (MS-ES) is a one-second period with one or 
more errored blocks or at least one defect.
MS-ESR Multiplex Section Errored Second Ratio (MS-ESR) is the ratio of errored 
seconds to total seconds in available time during a fixed measurement interval.
MS-SES Multiplex Section Severely Errored Second (MS-SES) is a one-second period 
that contains 30 percent or more errored blocks or at least one defect. SES is a 
subset of ES. For more information, refer to ITU-T G.829 Section 5.1.3.
MS-SESR Multiplex Section Severely Errored Second ratio (MS-SESR) is the ratio of 
SES to total seconds in available time during a fixed measurement interval.
MS-UAS Multiplex Section Unavailable Seconds (MS-UAS) is a count of the seconds 
when the section was unavailable. A section becomes unavailable when ten 
consecutive seconds occur that qualify as MS-SESs, and it continues to be 
unavailable until ten consecutive seconds occur that do not qualify as 
MS-SESs. When the condition is entered, MS-SESs decrement and then count 
toward MS-UAS.
RS-BBE Regenerator Section Background Block Error (RS-BBE) is an errored block 
not occurring as part of an SES.
RS-BBER Regenerator Section Background Block Error Ratio (RS-BBER) is the ratio of 
BBE to total blocks in available time during a fixed measurement interval. The 
count of total blocks excludes all blocks during SESs.
RS-EB Regenerator Section Errored Block (RS-EB) indicates that one or more bits are 
in error within a block.
RS-ES Regenerator Section Errored Second (RS-ES) is a one-second period with one 
or more errored blocks or at least one defect.
RS-ESR Regenerator Section Errored Second Ratio (RS-ESR) is the ratio of errored 
seconds to total seconds in available time during a fixed measurement interval.
RS-SES Regenerator Section Severely Errored Second (RS-SES) is a one-second 
period which contains 30 percent or more errored blocks or at least one defect. 
SES is a subset of ES.
RS-SESR Regenerator Section Severely Errored Second Ratio (RS-SESR) is the ratio of 
SES to total seconds in available time during a fixed measurement interval.
RS-UAS Regenerator Section Unavailable Second (RS-UAS) is a count of the seconds 
when the regenerator section was unavailable. A section becomes unavailable 
when ten consecutive seconds occur that qualify as RS-UASs, and it continues 
to be unavailable until ten consecutive seconds occur that do not qualify as 
RS-UASs.
Table 17-30 SDH PM Parameters (continued)
Parameter Definition