| 1. | Inbound Toll Free Service | Provides a toll free number or numbers for incoming calls (these numbers often share a line with a non-toll free number) |
| 2. | Information Provider | A company that offers pay-per-use information services, such as sports scores or financial market updates, via 900 or 976 phone numbers. |
| 3. | Information Services | Weather reports, news, soap opera updates, and other information provided as an option with some phone service plans. Fees are often charged for such services. |
| 4. | Integrated Service Digital Network | ISDNA high-capacity wireline used mainly for high-speed data transfer. |
| 5. | Integrated System | A system that handles analog and digital traffic over a single switched network. |
| 6. | InterLATA | Communication between LATAs. |
| 7. | Interexchange | Communication between two different LATAs. |
| 8. | Interexchange Carrier | IECA long distance company providing long-distance phone service between LECs and LATAs.. Any phone company providing phone service between local service areas of a state and to locations in other states. A company that provides long distance phone service between local exchange carriers (LECs, pronounced "lecks") and area codes outside a LEC's service area. AT&T, Sprint, and MCI WorldCom are examples of interexchange carriers. Also called IEC and IXC. |
| 9. | International | Communication between nations. |
| 10. | International Access Dialing Code | 011The prefix for dialing a number in another country; it is followed by a country code and the local phone number. Calls between the U.S. and Canada don't require use of this prefix. |
| 11. | International Direct Distance Dialing | The ability to directly dial a call to another country. |
| 12. | International Rate | The rate charged for making calls from the US to an international location. |
| 13. | Internet Service Provider | ISPProvides Internet connections to customers with PCs or other reception devices. The customers are usually billed for the service. The largest ISP is America Online (AOL). |
| 14. | Interstate | Between states. Interstate communications are regulated by the FCC. |
| 15. | IntraLATA | Communication within a Local Access Transport Area. LECs are allowed to handle these calls without an IEC. |
| 16. | IntraLATA Competition | The proposal to open local service areas to competition by long distance companies. |
| 17. | Intrastate | Communication within a single state. Intrastate communications are regulated by each state's PUC. |