Appendix C. Acronyms/AbbreviationsC-2 T3SU 300 User Manual 61200217L1-1DSU ................... data service unitDSX-1 ................ digital signal cross connect, level 1DTE ................... data terminal equipmentDTR ................... data terminal readyES ....................... errored secondsEXZ .................... excessive zerosFDL .................... facility datalinkFEBE .................. far end block errorHSSI .................. high-speed serial interfaceIP........................ internet protocolKA...................... keep aliveLAN ................... local area networkLCV ................... line coding violationLED.................... light emitting diodeLES..................... line errored secondsLL ....................... local loopbackLOS.................... loss of signalMBE................... M-bit errorsMbps ................. megabits per secondMIB.................... management information basems....................... millisecondNC...................... normally closedNI ....................... network interfaceNMS .................. network management systemNO ..................... normally openNRZ ................... non-return to zeroOCU................... office channel unitOOF ................... out of frameOOS................... out of service
