| API | Application Programming Interface |
| ASN.1 | Abstract Syntax Notation Number One |
| AS | Autonomous System |
| BGP4 | Border Gateway Protocol |
| CDR | Call Detail Record |
| CIM | Common Information Model |
| CLI | Command-Line Interface |
| CNC | Computer Numerical Control Machine |
| CO | Central Office |
| COM | Component Object Model |
| COS | Class of Service |
| COTS | Commercial Off-The-Shelf |
| CPE | Customer Premises Equipment |
| CTI | Computer Telephony Integration |
| DECT | Digital Enhanced Cordless Telecommunications |
| DEN | Directory-Enabled Networking |
| DES | Data Encryption Standard |
| DLCI | Data Link Connection Identifier |
| DMI | Desktop Management Interface |
| DNS | Domain Name System |
| DS | Differentiated Services |
| DSCP | Differentiated Services Code Point |
| DSL | Digital Subscriber Line |
| DTL | Designated Transit List |
| DWDM | Dense Wavelength Division Multiplexing |
| ECN | Explicit Congestion Notification |
| ELAN | Emulated LAN |
| EMS | Element Management System |
| FCAPS | Fault, Configuration, Accounting, Performance, and Security |
| FEC | Forwarding Equivalence Class |
| FR | Frame Relay |
| FTN | FEC-to-NHLFE |
| GMPLS | Generalized Multiprotocol Label Switching |
| IANA | Internet-Assigned Numbers Authority |
| IDL | Interface Definition Language |
| IETF | Internet Engineering Task Force |
| IN | Intelligent Networking |
| INTSERV | Integrated Services |
| IP | Internet Protocol |
| IS-IS | Intermediate System-Intermediate System |
| ISDN | Integrated Service Digital Network |
| ISP | Internet Service Provider |
| IT | Information Technology |
| J2EE | Java 2 Enterprise Edition |
| JDK | Java Development Kit |
| JDMK | Java Development Management Kit |
| JIT | Just-in-Time |
| JVM | Java Virtual Machine |
| L2TP | Layer 2 Tunneling Protocol |
| LDAP | Lightweight Directory Access Protocol |
| LER | Label Edge Router |
| LSP | Label Switched Path |
| LSR | Label Switching Router |
| MAP | Mobile Application Part |
| MD5 | Message Digest 5 |
| MIB | Management Information Base |
| MPLS | Multiprotocol Label Switching |
| MTP | Message Transfer Part |
| MVNO | Mobile Virtual Network Operator |
| NAP | Network Access Point |
| NE | Network Element |
| NGN | Next-Generation Network |
| NHLFE | Next-Hop Label Forwarding Entry |
| NIC | Network Interface Card |
| NMS | Network Management System |
| NOC | Network Operations Center |
| OID | Object Identifier |
| OOD | Object-Oriented Design |
| ORB | Object Request Broker |
| OSPF | Open Shortest Path First |
| OSI | Open Systems Interconnection |
| OSS | Operations Support System |
| PBNM | Policy-Based Network Management |
| PDP | Policy Decision Point |
| PDR | Performance Data Record |
| PDU | Protocol Data Unit |
| PEP | Policy Enforcement Point |
| PHB | Per-Hop-Behavior |
| PIB | Policy Information Base |
| PLC | Programmable Logic Controller |
| PNNI | Private Network-To-Network Interface |
| POP | Point-of-Presence |
| POTS | Plain Old Telephone Service |
| PSTN | Public Switched Telephone Network |
| PVC | Permanent Virtual Connection |
| PVX | Permanent Virtual Connection (Generic term ) |
| QA | Quality Assurance |
| QoS | Quality of Service |
| RADIUS | Remote Access Dial-In User Service |
| RAS | Remote Access Server |
| RFC | Request for Comment |
| RMI | Remote Method Invocation |
| RPC | Remote Procedure Call |
| SAN | Storage Area Network |
| SCCP | Signaling Connection Control Part |
| SDL | Specification and Description Language |
| SHA1 | US Secure Hash Algorithm 1 |
| SIN | Ships-in-the-Night |
| SLA | Service Level Agreement |
| SMS | Short Message Service |
| SNMP | Simple Network Management Protocol |
| SOAP | Simple Object Access Protocol |
| SP | Service Provider |
| SPPI | Structure of Policy Provisioning Information |
| SPVCC | Switched Permanent Virtual Channel Connection |
| SPVX | Generic Switched Permanent Virtual Circuit |
| SS7 | Signaling System Number 7 |
| TCAP | Transaction Capability Application Part |
| TCP | Transmission Control Protocol |
| TDM | Time Division Multiplexing |
| TL1 | Transaction Language One |
| TLS | Transparent LAN Service |
| TMN | Telecommunications Management Network |
| TOM | Telecommunications Operations Map |
| TOS | Type of Service |
| UML | Unified Modeling Language |
| USM | User-based Security Model |
| VCI | Virtual Channel Identifier |
| VLAN | Virtual Local Area Network |
| VoIP | Voice-over-IP |
| VPI | Virtual Path Identifier |
| WAN | Wide Area Network |
| XML | Extensible Markup Language |
