VeEX MPA, User Manual

Page: 833 / 842

Term Definitions
833
higher-rate signal, a parity check byte, a local orderwire channel for voice
communications between section terminating equipment, a data communications
channel for message-based network management and maintenance information, and a
user channel for network operator communications. See also
Section Terminating
Equipment .
Section Terminating Equipment (STE)
Equipment at either end of a Section span in a SONET network which either originates
the Section Overhead or terminates the Section Overhead.
SEF
Severely Errored Frame. A SONET defect that is the first indication of trouble in
detecting valid signal framing patterns. Four consecutive errored framing patterns
constitute an SEF defect.
SEFS
Severely Errored Frame Seconds. The number of seconds in which an entity has an
extremely high frame error rate or major defect.
Service Disruption
Measurement of service disruption intervals in the network. Statistics can be used to
determine how long it takes network equipment to react to a disruption event and switch
to a backup path.
SES
Severely Errored Seconds. The number of seconds in which an entity has an extremely
high error rate.
SES-L
Severely Errored Seconds - Line. This reports the duration of Severely Errored Seconds
on the incoming SONET signal. An SES is reported when 9,835 or more B2 errors
occur in one second or when a SEF, LOF, LOS, or AIS-L alarm occurs.
SES-LFE
This reports the duration when 9,835 or more REI-L errors are present at the far-end
LTE, or when a Line Remote Defect Indicator
(RDI-L) alarm is present.
SES-P
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