| A | B |
|---|
| MDF | Main Distribution Frame |
| MDI | Media Dependent Interface |
| MDIX | Media Dependent Interface Crossover |
| MIB | Management Information Base |
| MMF | Multimode Fiber |
| MPLS | Multi-Protocol Label Switching |
| MS-CHAP | Microsoft Challenge Handshake Authentication Protocol |
| MT-RJ | Mechanical Transfer-Registered Jack |
| MX | Mail Exchanger |
| NAT | Network Address Translation |
| NetBEUI | Network Basic Input/Output Extended User Interface |
| NetBIOS | Network Basic Input/Output System |
| NIC | Network Interface Card |
| nm | Nanometer |
| NNTP | Network News Transfer Protocol |
| NTP | Network Time Protocol |
| OCx | Optical Carrier |
| OS | Operating System |
| OSI | Open Systems Interconnect |
| OSPF | Open Shortest Path First |
