"AAL","ATM Adaption Layer"
"ACSE","Association Control Service Elements, ISO 8650"
"ADM","Add/Drop Multiplexer"
"ADPCM","Adaptive differential Pulse Code Modulation"
"ADSL","Asymmetric Digital Subscriber Line"
"AIS","Alarm Indication Signal"
"ALS","Automatic Laser Shutdown"
"AMI","Alternate Mark Inversion"
"ANSI","American National Standards Institute"
"AP","Access Point"
"APLL","Analog Phase Locked Loop"
"APS","Automatic Protection Switching"
"ARP","Ethernet Address Resolution Protocol, RFC 826"
"ASCII","American Standard Code for Information Interchange"
"ASN","Abstarct Syntax Notation"
"ATDM","Asynchronous Time Division Multiplex"
"ATM","Asynchroner Transfer Modus"
"AU","Administrativ Unit"
"AU-AIS","Administrative Unit Alarm Indication Signal"
"AUG","Administrativ Unit Group"
"AU-LOP","Administrative Unit Loss of Pointer"
"B3ZS","Binary with 3 Zeros Supression"
"B8ZS","Binary with 8 Zeros Supression"
"BBE","Background Block Error"
"BBER","Background Block Error Ratio"
"BER","Basic Encoding Rules"
"BER","Bit Error Rate"
"BIP","Bit Interleaved Parity"
"BIP-N","Bit Interleaved Parity N"
"BIS","Bringing-Into-Service"
"B-ISDN","Broadband-ISDN"
"BITS","Building Integrated Timing Supply"
"Br","Bridge(d)"
"BRI","Basic Rate Interface"
"BSC","Base Station Controller"
"BTS","Basic Transeiver Station"
"CAP","Carrierless Amplitude/Phase  Modulation"
"CAS","Channel Associated Signaling"
"CASE","Common Application Service Element"
"CBR","Constant Bit Rate"
"CC","Cross Connect"
"CCITT","International Telephone and Telegraph Consaltive Committee"
"CCR","Commitment, Concurrency and Recovery ISO 9804/5"
"CCS","Common Channel Signaling"
"CEC","Cell Error Control"
"CEPT","Committee European de Post et Telegraph"
"CI","Concatenation Indicator"
"CLP","Cell loss priority"
"CMI","Coded Mark Inversion"
"CMIP","Common Management Information Protocol"
"CMISE","Common Management Information Service"
"CMOT","Common Management Information Services and Protocol over TCP/IP"
"CMTT","Mutual Television Committee"
"CN","Corporate Network"
"CN","City Net"
"CP","Customer Premesis"
"CP","Connection Point"
"CPE","Customer Premises Equipment"
"CRC","Cyclic Redundancy Check"
"CSMA/CD","Carrier Sense Multiple Access with Collision Detection (Lan-T.)"
"DCC","Data Communication Channel"
"DCE","Data Circuit Terminating Equipment"
"DCN","Data Communication Network"
"DCS","Digital Cross Connect System"
"DDF","Digital Distribution Frame"
"DEE","Datenendeinrichtung"
"DLC","Digital Loop Carrier"
"DMT","Discrete Multitone Technology"
"DN","Distinguished Name"
"DPRing","Dedicatet Protected Ring"
"DQDB","Distributed Queue Dual Bus"
"DS","Degraded Second"
"DS1","Primary Rate Digital Signal"
"DTE","Data Terminal equipment"
"DšE","Datenbertragungseinrichtung"
"DWDM","Dense Wave Division Multiplex"
"DXC","Digital Cross Connect"
"E1","2,048Mbit/s"
"E2","8,4Mbit/s"
"E3","34,4Mbit/s"
"E4","139,2Mbit/s"
"EB","Errored Block"
"EBU","European Broadcasting Union"
"ECC","Embedded Control Channel"
"EDC","Error Detection Code"
"EDI","Electronic Data Interchange"
"EEC","European Economic Community"
"EFS","Error Free Second"
"EGP","Exterior Gateway Protocol, RFC 904"
"EML","Element Management Layer"
"EOW","Engineering Order Wire"
"E-R","Entity Relationship"
"ERT","Elementary Regenerator Section Termintion"
"ES","Errored Second"
"ES","End System"
"ESR","Errored Second Ratio"
"ETR","ETSI Technical Report"
"ETS","European Telecommunications Standard"
"ETSI","European Telecommunications Standards Institute"
"EWSD","Siemens Switching Technology"
"EXER-R","Exerciser-Ring"
"EXER-S","Exerciser-Span"
"FAS","Frame Alignment Signal"
"FAW","Frame Alignment Word"
"FDDI","Fiber Distributed Data Interface"
"FDM","Frequency Division Multiplex"
"FEBE","Far End Block Error"
"FEC","Forward Error Correction"
"FERF","Far End Receiver Failure"
"FMC","Fixed-Mobile-Convergence"
"FS","Frontier Station"
"FS-P","Forced Switch to Protection"
"FS-R","Forced Switched Working to Protection-Ring"
"FS-S","Forced Switched Working to Protection-Span"
"FS-W","Forced Switch to Working"
"FTAM","File Transfer Access and Management, ISO 8571"
"FTP","File Transfer Protocol"
"GFC","Generic Flow Control"
"HDB3","High Density Bipolar with maximum of 3 zeros"
"HDSL","High Speed Digital Subscriber Loop"
"HDTV","High Definition Television"
"HEC","Header Error Check"
"HICOM","Siemens Telephony Equipment"
"HO","Higher Order"
"HOP","Higher Order Path"
"HOVC","Higher Order Virtual Container"
"HP-DEG","Higher Order Path Degraded"
"HP-EXC","Higher Order Path Excessive Errors"
"HP-SSF","Higher Order Path Server Signal Fail"
"HP-TIM","Higher Order Path Trace Identifier Mismatch"
"HP-UNEQ","Higher Order Path Unequipped"
"HRP","Hypothetical Reference Path"
"HVC","High Order Virtual Container"
"HW","Hardware"
"I/D","Increment/Decrement"
"IAB","Internet Activities Board"
"IANA","Internet Assigned Numbers"
"IB","International Border"
"ICI","Interface Control Information"
"ICMP","Internet Control Message Protocol, RFC 792"
"ICPCE","Inter-Country Path Core Element"
"ID","Identification"
"IDTC","International Digital Transmission Centre"
"IDU","Interface Data Unit"
"IEC","International Exchange Carriers"
"IEEE","Institution of Electrical and Electronic Engineers"
"IETF","Internet Engineering Task Force"
"I-ETS","Interim ETS"
"IG","International Gateway"
"IG","International Gateway"
"IMF","Infant Mortility Factor"
"INWG","Internet Working Group"
"IP","Intelligent Peripheral"
"IP","Internet Protocol"
"IPCE","International Path Core Element"
"IRIS","Intelligent Responder to ISDN"
"IS","Intermediate System"
"ISC","International Switching Centre"
"ISDN","Integrated Services Digital Network"
"ISM","In-Service Monitoring"
"ISO","International Organisation for Standardization"
"ISP","Internet Service Provider"
"IWF","Interworking Function"
"JTM","Job Transfer and Manipulation, ISO 8831/2"
"LAN","Local Area Network"
"LATA","Local Access and Transit Areas"
"LEC","Local Exchange Carriers"
"LED","Light Emitting Diode"
"LLP","Lightweight Presentation Protocol"
"LO","Lower Order"
"LOF","Loss of Frame Alignment"
"LOF","Loss of Frame"
"LOI","Letter Of Intent"
"LOP","Low Order Path"
"LOS","Loss of Signal"
"LOVC","Lower Order Virtual Container"
"LP","Lockout of Protection"
"LP-DEG","Lower Order Path Degraded"
"LP-EXC","Lower Order Path Excessive Errors"
"LPF","Low Pass Filter"
"LP-S","Lockout of Protection-Span"
"LP-SSF","Lower Order Path Server Signal Fail"
"LP-TIM","Lower Order Path Trace Identifier Mismatch"
"LP-UNEQ","Lower Order Path Unequipped"
"LSS","Link Status Signal"
"LT","Line Terminal"
"LTBER","Long Term Bit Error Rate"
"LVC","Lower Order Virtual Containers"
"LXC","Lokaler CC"
"M&I","Maintenance & Installation"
"MA","Management Agent"
"MACF","Multiple Association Control Function"
"MAN","Metropolitan Area Network"
"MBS","Monitoring Block Size"
"MI","Management Interface (Nokia PDH Management)"
"MIB","Management Information Base"
"MLM","Multilongitudinal Mode"
"MO","Managed Objects"
"MOTIS","Message Oriented Text Interchange System, ISO 8505/8883"
"MRTIE","Maximum Relative Time Interval Error"
"MS","Multiplex Section"
"MSA","Multiplex Section Adaptation"
"MSC","Mobile Switching Center"
"MSOH","Multiplexer Section Overhead"
"MSP","Multiplex Section Protection"
"MS-P","Manual Switch to Protection"
"MSPA","Multiplex Section Protection Adaptation"
"MSPG","Multiplex Section Protection Group"
"MSPT","Multiplex Section Protection Termination"
"MS-R","Manual Switch-Ring"
"MS-S","Manual Switch-Span"
"MST","Multiplex Section Termination"
"MS-W","Manual Switch to Working"
"MTBF","Mean Time Between Failure"
"MTIE","Maximum Time Intervall Error"
"MTTR","Mean Time To Restore"
"MUX","Multiplexer"
"NA","Network Aspects"
"NDF","New Data Flag"
"NDS","Network Documentation System"
"NE","Network Element"
"NFS","Network File System"
"NMC","Network Management Center"
"NMF","Network Management Forum"
"NML","Network  Management Layer"
"NMS","Network Management Station"
"NNI","Network Node Interface"
"NOC","Network Operational Center"
"NP","Network Performance"
"NPCE","National Path Core Element"
"NPE","National Path Element"
"NPI","Null Pointer Indicator"
"NR","No Request"
"NRZ","Non Return to Zero"
"NSAP","Network Service Access Point"
"OAM","Operation and Maintenance"
"OAM","Operation Administration and Maintenance"
"OAM&P","Operations, Administration, Maintenance and Provisioning"
"OC-N","Optical Channel Level N"
"ODF","Optical Distributed Frame"
"ODP","Open Distributed Processing"
"OH","Overhead"
"OHA","Overhaed Access"
"OOF","Out Of Frame"
"OS","Operation System(s)"
"OS","Optical Section"
"OSI","Open Systems Interconnection"
"PAD","Packet Assembly Disassembly"
"PAE","Path Access Element"
"PCE","Path Core Element"
"PCI","Protocol Control Information"
"PCM","Pulscodemodulation"
"PCN","Cellular Digital Mobile Network"
"PCS","Plesiochronous Connection Supervision"
"PDH","Plesiochronous Digital Hierarchy"
"PDU","Protocol Data Unit"
"PE","Path Element"
"PEP","Path End Point"
"PJE","Pointer Justification Event"
"PMD","Polarization Mode Dispersion"
"POH","Path Overhead"
"POI","Point Of Interconnect"
"POM","Path Overhead Monitoring"
"PoP","Point of Presence"
"POT","Point of Transit"
"PRBS","Pseudo-Random Bit Sequence"
"PRC","Primary Reference Clock"
"PS","Protection Switch"
"PSTN","Public Switched Telephone Network"
"PTI","Payload Type Identifier"
"QoS","Quality of Service"
"RAI","Remote Alarm Indication"
"RBS","Robbed Bit Signaling"
"RDA","Remote Database Access, ISO 9579"
"RDI","Remote Defect Indication (former FERF)"
"RDN","Relative Distinguished Name"
"REI","Remote Error Indication"
"RFC","Request For Comment"
"RLT","Regenerated Line Termination"
"RMS","Root Mean Square"
"ROSE","Remote Operations Service Elements, ISO 9072"
"RPO","Reference Performance Objectives"
"RR-R","Reverse Request-Ring"
"RR-S","Reverse Request-Span"
"RS","Regenerator Section"
"RSOH","Regenerator Section Overhead"
"RST","Regenerator Section Termination"
"RTIE","Relative Time Interval Error"
"RTSE","Reliable Transfer Service Elements, ISO 9066"
"RUAE","Remote User Access Equipment"
"RZ","Return to Zero"
"SA","Service Affecting"
"SACF","Single Association Control Function"
"SAO","Single Association Object"
"SASE","Specific Application Service Elements"
"SAW","Surface Acoustic Wave"
"SD","Signal Degrade"
"SDCN","SDH-DCN"
"SDH","Synchronous Digital Hierarchy"
"SDP","Severely Disturbed Period"
"SD-P","Signal Degrade of the Protection Channels"
"SD-R","Signal Degrade-Ring"
"SD-S","Signal Degrade-Span"
"SDU","Service Data Unit"
"SE","Service Elements"
"SEC","Synchronous equipment clock"
"SES","Severely Errored Second"
"SESR","Severely Errored Second Ratio"
"SETPI","Synchronous Equipment Timing Physical Interface"
"SETS","Synchronous Equipment Timing Source"
"SF","Signal Fail"
"SF-R","Signal Fail-Ring"
"SF-S","Signal Fail-Span"
"SIE","Short Interrupt Event"
"SIE","Short Interruption Event"
"SKIP","Simple Key management for Internet Protocol"
"SLM","Single Longitudinal Mode"
"SMS","Management Subnetwork"
"SMS","Service Management System"
"SMTP","Simple Mail Transfer Protocol"
"SN","Service Node"
"SNA","Systems Network Architecture"
"SNC","SubNetwork Connection"
"SNC/I","SubNetwork Connection Protection with Inherent Monitoring"
"SNC/N","SubNetwork Connection Protection with Non-intrusive Monitoring"
"SNCP","Subnetwork Connection Protection"
"SNCP/I","Subnetwork Connection Protection/Inherent Monitoring"
"SNML","{Subnetwork Management Layer}"
"SNMP","Simple Network Management Protocol, RFC 1067"
"SNMS","{Subnetwork Management System}"
"SOH","Section Overhead"
"SONET","Synchronous Optical Network"
"SPE","Synchronous Payload Envelope"
"SPI","SDH Physical Interface"
"SPRing","Shared Protection Ring"
"SSF","Server Signal Fail"
"SSP","Service Switching Point"
"SSU","Synchronisation Supply Unit"
"STDM","Synchronous Time Division Multiplex"
"STM-N","Synchronous Transport Module Level N"
"STM-N","Synchronous Transport Modul Level N"
"STP","Single Transfer Point"
"STS-N","Synchronous Transport Signal Level N"
"SW","Software"
"Sw","Switch(ed)"
"TCM","Tandem Connection Monitoring"
"TCP","Termination Connection Point"
"TCP","Transfer Control Protocol (verbindungsorientiert)"
"TDEV","Time Deviation"
"TDM","Time Division Multiplex"
"Telco","Telecommunications Company"
"TELNET","Telnet Virtual Terminal Protocol"
"TIC","Terminal International Centre"
"TMC","Transmission Management Computer"
"TMN","Telcommunications Management Network"
"TMS","Transmission Management System"
"TP","Transmission Path"
"TP","Termination Point"
"TSI","Time Slot Interchange"
"TST","Time Space Time"
"TT","Trouble Ticket"
"TTP","Trail Termination Point"
"TTPId","Trail Termination Point Identifiers"
"TTS","Trouble Ticket System"
"TU","Tributary Unit"
"TUG","Tributary Unit Group"
"UAE","User Access Equipment"
"UAS","Unavailable Second"
"UDP","User Datagramm Protocol"
"UI","Unit Interval"
"UNI","User Network Interface"
"URL","Universal Resource Locator"
"USV","Unterbrechungsfreie Stromversorgung"
"UT","Unavailable Time"
"VC","Virtual Container"
"VCI","Virtual Channel Identifier"
"VP","Virtual Path"
"VPI","Virtual Path Identifier"
"VT","Virtual Tributary"
"VTG","Virtual Tribtutary Group"
"WAN","Wide Area Network"
"WDM","Wave Division Multiplex"
"WSCP","Wireless Service Control Point"
"WTR","Wait to restore"
"WWW","World Wide Web"