| AAL | ATM Adaptation Layer |
| APN | Actual Private Network |
| ARIS | Aggregate Route -based IP Switching |
| ARP | Address Resolution Protocol |
| ATM | Asynchronous Transfer Mode |
| BCE | BCE Enterprises |
| BGP | Border Gateway Protocol |
| BWS | Bandwidth Select |
| CE | Customer Edge (or Customer Equipment) |
| CLIP | Classical IP and ARP over ATM |
| CPE | Customer Premises (or Provided) Equipment |
| DLL | Data Link Layer (L2) |
| FR | Frame Relay |
| ICMP | Internet Control Message Protocol |
| IEEE | Institute of Electrical and Electronics Engineers |
| IETF | Internet Engineering Task Force |
| IFMP | Ipsilon's Flow Management Protocol |
| IGP | Interior Gateway Protocol |
| ILM | Incoming Label Map |
| ION | Internetworking over NBMA |
| IP | Internet Protocol |
| I-PNNI | Integrated PNNI |
| IPv4 | IP version 4 |
| IPv6 | IP version 6 |
| ISP | Internet Service Provider |
| LAN | Local Area Network |
| LANE | LAN emulation |
| LC-ATM | Label Switching Controlled-ATM |
| LC-FR | Label Switching Controlled-Frame Relay |
| LDP | Label Distribution Protocol1 |
| LER | Label Edge Router |
| LIS | Logical IP Subnet |
| L-LSP | Label-only-inferred-PSC LSP |
| LSP | Label-Switched Path |
| LSR | Label Switching (switched or switch) Router |
| MIB | Management Information Base |
| MPLS | Multiprotocol Label Switching |
| MPOA | Multi-Protocol over ATM |
| NBMA | Non-Broadcast Multiple Access (networks) |
| NHLFE | Next Hop Label Forwarding Entry |
| NHRP | Next Hop Resolution Protocol |
| NHS | Next Hop Server |
| OSI | Open Systems Interconnection |
| OSPF | Open Shortest Path First |
| PAR | PNNI augmented routing |
| PDU | Protocol Data Unit |
| PE | Provider Edge |
| PHB | Per-Hop Behavior |
| PL | Private Line |
| PNNI | Private Network-to-Network Interface |
| POS | Packet over (on) SONET |
| PPP | Point-to-Point Protocol |
| PSC | PHB Scheduling Class |
| PSTN | Public Switched Telephone (Telephony) Network |
| PVC | Permanent Virtual Circuit |
| QoS | Quality of Service |
| ROLC | Routing Over Large Clouds |
| RSVP | Reservation Protocol |
| SAFI | Subsequent Address Family Identifier |
| SE | Shared Explicit |
| SITA | Switching IP Through ATM |
| SM | Switched Minutes |
| SNPA | Sub-Network Points of Attachment |
| SONET | Synchronous Optical Network |
| STII | Internet Stream Protocol version II |
| SVC | Switched Virtual Circuit |
| TDP | Tag Distribution Protocol |
| TE | Traffic Engineering |
| TLV | Type-Length-Value |
| TM | Traffic Management |
| VC | Virtual Circuit |
VCI / VCID |
Virtual Circuit Identifier |
| VP | Virtual Path |
| VPCI | Virtual Path and Circuit Identifier |
VPI |
Virtual Path Identifier |
| VPN | Virtual Private Network |
| WLS | Wavelength Select |
