GL-18
Issue 9 October 1998
363-206-204
GLOSSARY
Self-Healing
Ring architecture in which two or more fibers are used to provide route diversity.
Node failures only affect traffic dropped at the failed node.
SEFS
Severely Errored Frame Seconds.
SEO
Single-Ended Operations — The maintenance capability that provides remote
access to all DDM-2000 systems from a single location over the DCC.
Service Line
On a DDM-2000 OC-3 system, a service (or "working") line is a pair of fibers (one
transmit and one receive) that terminate on an OLIU circuit pack in the
main-1,
or
fn-a-1
, or
fn-b-1
, or
fn-c-1
slot. As defined by the SONET standard, the
SONET APS channel is not defined on a service (or "working") line. (See "Protec-
tion Line.")
SES
Severely Errored Seconds — This performance monitoring parameter is a second
in which a signal failure occurs, or more than a preset amount of coding violations
(dependent on the type of signal) occurs.
SF
Super Frame (format for DS1 signal).
Shelf ID
A switch settable parameter with values of from 1 to 8. Used to log into a selected
shelf in a bay using the CIT.
SID
System Identification. Also, Shelf Identification. See NOTE, 10-12.
Site ID
A switch settable parameter with values of from 1 to 8. Displayed on SYSCTL cir-
cuit pack to indicate to which site the user panel alarms and LEDs apply.
SONET
Synchronous Optical Network.
SPE
Synchronous Payload Envelope.
SPE STS-1
Synchronous Payload Envelope — A 125-microsecond frame structure composed
of STS path overhead and the STS-1 payload.
SRD
Software Release Description.