| Abbreviation | Definition |
|---|---|
| IEC | InterExchange Carrier |
| IEEE | Institute of Electrical and Electronics Engineers |
| IEPL | Internatioal Ethernet Private Line |
| IEPL | International Ethernet Private Line |
| IESS | INTELSAT Earth Station Standard |
| IETE | Institute of Electronics and Telecommunication Engineers |
| IFLS | Inter-Frequency Load Sharing |
| IG | Interface Group |
| IIS | Internet Information Services |
| IKI | Institut Kosmitcheskikh Issledovanii |
| ILD | International Long Distance |
| ILETS | Idaho Law Enforcement Telecommunication System |
| ILETS | International Law Enforcement Telecommunications Seminar |
| ILF | Initial License Fee |
| ILQ | Inbound Link Quality |
| ILRM | Interim Local Management Interface |
| IMA | Inverse Multiplexing for ATM (Asynchronous Transmission Mode) |
| IMC | Intermediate Metal Conduit |
| IMEI | International Mobile Equipment Identity |
| IMM | Interactive Mobile Media |