| Abbreviation | Definition |
|---|---|
| NML | Network Management Layer |
| NMP | Network Management Protocol |
| NMSI | National Mobile Station Identity |
| NMT | Nordic Mobile Telephony |
| NMT | Nordisk MobilTelefoni |
| NNG | National Number Group |
| NNI | Network Node Interface |
| NNI | Network-to-Network Interface |
| NNP | National Numbering Plan |
| NOC | Northern Old Carrier |
| NOF | NetObjects Fusion |
| NOL | Nokia On-Line |
| NOL | Number One Line |
| NOLC | NO Longer Connected |
| NOTE | Network Office Terminating Equipment |
| NPA | Numbering Plan Area |
| NPA | Numeral Prefix Allocation |
| NPAC | Number Portability Administration Center |
| NPD | Network Protective Device |
| NPDU | Network Protocol Data Unit |