| AA | Administrative Authority |
| AAL | ATM adaptation layer |
| AAL1 | connection oriented at constant bit rate (e.g. DS1 DS3) |
| AAl1SAR | |
| AAL2 | connection oriented at variable bit rate (e.g. some video) |
| AAL3/4 | CO or CL at variable bit rate |
| AAL5 | CO or CL at variable bit rate (lean: no error recovery) |
| ABR | Available Bit rate |
| ACF | a DQDB header field |
| ACR | Allowed cell rate |
| ACR | Average cell rate |
| ACSE | Association Control Service Element |
| ADSL | Asymetrical Digital Subscriber Loop |
| ADTF | Allowed cell rate Decrease Time Factor |
| AESA | ATM End Station Address |
| AFI | Authority and Format Identifier |
| AINI | ATM Inter-Network Interface |
| AIS | Alarm Indication Signal |
| AMA | Automatic message accounting |
| ANSI | American National Standards Institute |
| APC | Adjacent Point Code |
| API | application programmers' interface |
| ARP | address resolution protocol |
| AS | Autonomous System |
| ASN.1 | Abstract Syntax Notation One |
| ASP | ATM Service Provider |
| AT | Abatement-congestion threshold |
| ATM | Adobe Type Manager |
| ATM | Asynchronous Transfer mode |
| ATM | Automatic Teller Machine |
| ATMARP | Address registration protocol over ATM |
| ATMF | ATM Forum |
| AToMIS | ATM Oriented Multimedia Information System (NEC's product name) |
| AToMMIB | ATM SONET MIB. (o from Sonet) (AToM meaning small) |
| ATOMVIEW | NEC name for NMS (both product and prototype) |
| BAF | Bellcore AMA format |
| BALUN | Balanced to Unbalanced impedance matching unit |
| BCN | broadcast channel number |
| BER | Bit error ratio |
| BGAK | Begin acknowledge (PDU) |
| BGN | Begin (PDU) |
| BHLI | Broadband Higher Layer Information |
| BGREJ | Begin rejected (PDU) |
| B-ICI | Broadband Inter(-exchange) Carrier Interface |
| B-ISSI | Broadband inter-switching system interface |
| B-ISUP | Broadband ISDN User Part |
| BIP | Byte Interleaved Parity (BIP-8 BIP-24) |
| BISDN | Broadband Integrated Services Digital Network |
| BLLI | Broadband Low Layer information |
| BMUX | Basic rate Multiplexor |
| BNA | Broadband network administrator |
| BOM | Beginning of message |
| BOMS | Beginning of message segment |
| BPN | broadcast packet network |
| BPV | Bipolar violations |
| BRDP | BPN reliable datagram protocol |
| BSS | Broadband switching system |
| BT | Burst tolerance |
| BTC | broadcast translation circuit |
| BTAG | Beginning TAG |
| BVPN | broadband virtual private network |
| CAC | Call access control |
| CAC | Connection admission control |
| CBO | Continuous bit-stream-oriented |
| CBR | Constant bit rate |
| CCITT | International Consultative Committee for Telephone and Telegraph |
| CDF | Cutoff decrease factor |
| CDV | Cell delay variation |
| CDVT | Cell delay variation tolerance |
| CE | Connection end-point |
| CEI | Connection end-point identifier |
| CER | Cell error ratio |
| CES | Circuit emulation service |
| CFA | carrier failure alarm |
| CgPN | Calling party number |
| CIR | Committed Information rate |
| CIC | Carrier identification code |
| CIP | Carrier identification parameter |
| CLEI | Common language equipment identifier |
| CLNP | Connection-less network protocol |
| CLP | Cell Loss Priority |
| CLR | Cell loss ratio |
| CM | Configuration Management |
| CMAP | connection management access protocol |
| CMIP | Common Management Information Protocol |
| CMIS | Common Management Information Service |
| CMISE | Common Management Information Service Element |
| CMMO | connection management managed object |
| CMNP | connection management network protocol |
| CMOL | CMIP over LLC |
| CMOT | CMIP over TCP/IP |
| CMR | Cell mis-insertion rate |
| CN | copy network |
| CNM | (ATM) Customer Network Management |
| CNR | Complex Node Representation |
| COM | Continuation of message |
| COMS | Continuation of message segment |
| CP | Common Part |
| CP | control processor |
| CPCS | Common Part convergence sub-layer |
| CPCS-CI | Common Part convergence sub-layer congestion indicator |
| CPE | Customer premises equipment |
| CPN | Customer premises network |
| CR | Conditional requirement |
| CRC | cyclic redundancy check |
| CRM | Cell rate margin |
| CRS | Cell relay service |
| CS | Convergence sublayer |
| CTD | Cell transfer delay |
| DBMS | Database management system |
| DCC | Data Country code |
| DFI | Domain specific part Format Identifier |
| DPC | Destination point code |
| DQDB | Distributed queue dual bus |
| DS1 | T1 interface 1.544 Mbps |
| DS3 | (Digital Signal 3) T3 interface 44.736Mbps |
| DSP | Domain specific part |
| DSU | Data Service UNIT |
| DTL | Designated transit list |
| DXI | Data exchange interface |
| E1 E2 E3 E4 | G703I/f E1@2.048Mbps E2@8.448Mbps E3@34.368Mbps E4 139Mbps |
| EFD | Event Forwarding Discriminator |
| EGP | Exterior Gateway protocol |
| EL | Element Layer |
| EML | Element management layer |
| ES | End system (e.g. a host) |
| ESI | End System Identifier |
| ETD | Enforcement traffic descriptor |
| ETSI | European Telecommunications Standards Institute |
| FAN | fanout field |
| FDDI | fibre distributed data interface |
| FDM | Frequency division multiplexing |
| FEC | forward error correction |
| FIFO | first-in first-out |
| FM | Fault Management |
| FR | Frame relay |
| FRS | Frame relay service |
| FSM | Finite state machine |
| FTAM | File transfer access and management |
| GFC | Generic flow control |
| GFR | Guaranteed Frame Rate (ATM Forum - UBR with minimum bandwidth guarantee) |
| GFR | Giant F***ing Router |
| GCAC | Generic connection admission control |
| GCRA | Generic cell rate algorithm |
| GUI | Graphical User interface |
| HEC | header error control |
| HIPPI | High Performance Parallel Interface |
| HPSN | High performance scalable networking |
| IAB | Internet activities board |
| ICD | International Code Designator |
| IDI | Initial domain identifier |
| IDP | Initial domain part |
| IDU | Interface data unit |
| ID | Identifier |
| IE | Information element |
| IETF | Internet engineering task force? |
| EFCI | Explicit forward cingestion indication |
| ERM | Explicit rate marking |
| IG | Information group |
| IGP | Internal Gateway Protocol |
| IMS | Interface message specification (NEC) |
| ILMI | Interim Local Management Interface |
| INA | Bellcore information network architecture |
| INI | Internode interface (replacement for NNI node-node and node to network i/f) |
| IP | Internet protocol |
| IPL | Initial Program load |
| IS | Intermediate system (e.g. a router (which isn't end point of IP connection)) |
| ISDN | Integrated Services Digital Network |
| ISO | International organisation for standardisation |
| ITU | International Telecommunications Union |
| LAN | Local area network |
| LATA | Local Access and Transport Area |
| LATM | Local ATM |
| LCD | Loss of Cell Delineation |
| LCV | line code violation |
| LE | LAN Emulation |
| LEC | LE Client |
| LEH | LE Headrer |
| LES | LE Server |
| LES | Line error seconds |
| LGN | Logical Group Node |
| LIS | Logically independent IP subnet |
| LLC | Logical link control |
| LM | Layer management |
| LOF | Loss of Frame |
| LOP | Loss Of Pointer |
| LOS | Loss of Signal |
| LUNI | LAN Emulation user to network interface |
| M1 | ATM Forum managment I/Fs User - Public |
| M2 | ATM Forum managment I/Fs Private ATM network mgmt |
| M3 | ATM Forum managment I/Fs Customer network management of Public ATM svc |
| M4 | ATM Forum managment I/Fs Public ATM network mgmt |
| M5 | ATM Forum managment I/Fs Public-Public network mgmt |
| MAC | Media access control |
| MARS | Multicast address resolution server |
| MC | machine congestion (level) |
| MaxCR | Maximum Cell Rate |
| MCLR | Maximum cell loss ration |
| MCR | Minumum cell rate |
| MCTD | Mean cell transfer delay |
| MCDV | Mean cell delay variation |
| MIB | Management information base |
| MIOX25 | Multiprotocol Interconnect over X.25 and ISDN (RFC1356) |
| MLA | Multi-letter acronym |
| MOSPF | Multicast open shortest path first |
| MPOA | ATM Forum Multiprotocol over ATM |
| MS | Manhattan Street |
| MTBF | Mean time between failure |
| MTTR | Mean time to repair |
| MTP3 | Message Transfer Part level 3 |
| NARP | NBMA Address registration protocol |
| NAS | NBMA ARP Server |
| NBMA | Non-Broadcast Multi-Access link layer |
| NCCI | Network call correlation identifier |
| NCL | Network communication link |
| NE | Network Element |
| NEL | Network Element Layer |
| NEML | Network Element Management Layer |
| NHRP | NMBA Next Hop Resolution Protocol |
| NHS | Next Hop Server |
| NLPID | Network Layer Protocol ID |
| NM | (ATM) Network management |
| NM | Node management |
| NML | Network Management Layer |
| NMS | Network management system |
| NNI | network-network interface |
| NPC | Network Parameter Control |
| NSAP | Network (Layer) Service Access Point |
| OAM | Operation and Maintenance cell |
| OC | Optical Carrier |
| OC3 OC12 OC48 | Sonet Optical signal at different speeds (OC3=155.52 OC12=622Mb/s) OCnn nn/19.29=>GBPS (OC-1 3 9 12 18 24 36 48) |
| OCD | Out of Cell Delineation |
| OLIP | Originating line information parameter |
| OPC | Originating point code |
| OSI | Open systems interconnect |
| OSPF | Open Shortest Path First(RFC1131.ps) |
| PCM | Pulse code modulation |
| PCR | Peak Cell Rate |
| PDH | Plesiochronous? Digital Hierarchy |
| PDU | Protocol data unit |
| PG | Peer group |
| PGL | Peer group leader |
| PHY | Physical layer |
| PLCP | Physical Layer Convergence Procedure |
| PM | Performance Management |
| PMD | physical medium dependent |
| PNNI | Private network-network interface |
| PNNI | Public NNI (not relevant to us) |
| PP | packet processor protocol |
| PP | port processor |
| PRM | Protocol Reference model |
| PSE | packet switch element |
| PSTN | public switched telephone network? |
| PT | payload type |
| PTI | Payload type identifier |
| PTSE | PNNI Topology State element |
| PTSP | PNNI Topology State packet |
| PVC | Permanent virtual circuit |
| PVCC | Permanent virtual channel connectio |
| PVPC | Permanent virtual path connection |
| QoS | Quality of Service |
| RAIG | Resource availability information group |
| RCC | Routing control channel |
| RD | Routing Domain |
| RDI | Remote Defect Identification |
| RMON | Remote network monitoring |
| RN | routing network |
| ROSE | Remote operation service element |
| RPC | remote procedure call |
| RSVP | Resource ReSerVation Protocol |
| RTSE | Reliable transfer service element |
| SAAL | Signalling AAL |
| SAP | Service access point |
| SAR | segmentation and reassembly |
| SCR | Sustainable Cell Rate |
| SDH | Synchronous digital hierarchy |
| SDU | Service data unit |
| SEAL | Simple and efficient adaptation layer |
| SFUP | switch fabric update protocol |
| SIR | Sustained Information rate |
| SM | Security management |
| SM | Session management |
| SMF | Systems management function |
| SMFA | Systems management functional area |
| SMDS | switched multi-megabit data service |
| SMI | Structure of Management Information (RFC1442 also 1445 1448) |
| SMI | switch module interface |
| SMP | Simple management protocol (SNMPv2?) |
| SNPA | SubNetwork point of Attachment |
| SNAP | SubNetwork Attachment Point(see IEEE 802.1a) |
| SNARE | Sub Network Address Resolution Entity |
| SNI | Subscriber Network Interface |
| SNMP | Simple network management protocol |
| SNPA | Subnetwork Point of Attachment |
| SONET | Synchronous optical network |
| SONETVT | SONET Virtual Tributary |
| SPANS | (Fore systems') simple protocol for ATM network signalling |
| SS | Switching system |
| SS7 | Signalling System Number 7 |
| SSCOP | Service Specific Connection Oriented Protocol |
| SSCF | Service Specific Coordination Function |
| SSCS | Service Specific convergence sub-layer |
| SSMO | switch side managed object |
| STM | Synchronous transfer mode |
| STS-3c | Synchronous Transport Signal 3c |
| SVC | Switched virtual circuit |
| T3/DS-3 | 45 Mbps DS3 physical layer |
| TAXI | Transparent Asynchronous Transmitter/Receiver Interface (100 M bps 4B/5B) |
| TC | Transmission convergence |
| TCP/IP | Transmission control protocol/Internet protocol |
| TDM | Time division multiplexing |
| TLA | Three letter acronym |
| TLV | Type length value |
| TMN | Telecommunications Management Network |
| TP | Termination Point |
| UBR | Unspecified Bit Rate |
| UDP | User datagram protocol |
| ULIA | Uplink information attribute |
| UME | UNI Management entity |
| UNI | User network interface |
| UPC | Usage parameter control |
| UTP | Unshielded Twisted Pair |
| VBR | Variable Bit Rate |
| VC | Virtual channel (NOT circuit) |
| VCC | virtual channel connection |
| VCI | (LATM MIB) Virtual circuit ID |
| VCI | virtual channel identifier |
| VCL | Virtual channel link |
| VCS | Virtual channel switch |
| VF | Variance factor |
| VLAN | Virtual LANs (appear same on MAC layer segment?) |
| VP | Virtual path (unidirectional logical association or bundle of VCs) |
| VPC | Virtual path connection |
| VPI | VP identifier |
| VPCI | Virtual path connection identifier |
| VPL | Virtual path link |
| VPN | virtual private network |
| VPT | Virtual path terminator |
| VS/VD | Virtual source/virtual destination (as in segmented VS/VD & hop-by-hop VS/VD) |
| WATM | Wide area ATM (subnet model) |
| WDM | |
| XDR | external data representation |
| XNS | |