EXFO FTB-800 Series for FTB-1 - Manual (Page 321)

Test Results
NetBlazer 311
Performance Monitoring
Near-End

EFS (Error Free Second) (G.821, G.826, G.828, and G.829): Gives the
number of seconds within which no error occurred.

EC (Error Count) (G.821 only): Gives the number of bit errors.

EB (Errored Block) (G.826, G.828, and G.829): Gives the count of
blocks in which one or more bits are in error.

ES (Errored Second)
For G.821, and M.2100 OOSM: Gives the number of seconds within
which one or more bit error occurred, or during which Loss Of Signal
(LOS) or AIS is detected.
For G.826, G.828, G.829, M.2100 ISM, and M.2101: Gives the number
of seconds within which one or more anomalies (FAS (DSn/PDH), EB,
etc.) occurred, or at least one defect occurred.

SES (Severely Errored Second)
For G.821, and M.2100 OOSM: Gives the number of seconds within
which a bit error ratio is  10
-3
, or during which one defect (LOS/AIS) is
detected.
For G.826, G.828, G.829 and M.2101: Gives the number of seconds
within which anomalies (FAS (DSn/PDH), EB, etc.) are  X% or at least
one defect occurred. X = 30% for DSn/PDH signals; see the following
table for SONET/SDH signals SES threshold.
OC-1
STS-1e
STM-0
STM-0e
OC-3
STS-3e
STM-1
STM-1e
OC-12
STM-4
OC-48
STM-16
OC-192
STM-64
Path 30% 30% 30% 30% 30%
Line/MS 15% 15% 25% 30% 30%
Section/RS 10% 30% 30% 30% 30%