电信专业英英词典I-2（在线收听）

　　International Organization for Standardization (ISO)

　　ISO is a worldwide federation of national standards bodies (ISO National Bodies). The work of preparing international standards is normally carried out through ISO technical committees. Draft proposals for international standards adopted by the technical committees are circulated to the National Bodies for approval before their acceptance as Draft International Standards by the committee.

　　Internet

　　The internet is a large collection of connected networks, primarily in the United States, running the Internet suite of protocols. Sometimes referred to as the DARPA Internet, NSF/DARPA In ternet, or the Federal Research Network.

　　Internet suite of protocols

　　The internet suite of protocols is a collection of computer-communication protocols originally developed under DARPA sponsorship, including the transmission control protocol/internet protocol (TCP/IP).

　　Interoffice Channel

　　In LEC tariffs, Interoffice Channel is the channel connecting two serving COs (more accurately serving wire centers). In IXC tariffs, the channel connecting two serving IXC POPs, interoffice transmission facilities used to connect LEC switching systems.

　　Intra-LATA

　　Intra-LATA are services, revenues, functions, etc., that relate to telecommunications originating and terminating within a single LATA (the domain of LECs).

　　IOC

　　interoffice channel

　　IPX

　　internetwork packet exchange

　　IP

　　internet protocol

　　ISDN

　　integrated services digital network

　　Isochronous Signals

　　Isochronous Signals are periodic signals in which the time interval that separates any two corresponding significant occurrences or level transitions is always equal to some unit interval or a multiple of that unit interval. For example, in digitized voice signals, ideally voice samples occur isochronously at precisely the sampling interval or frame rate. Packet data signals are not isochronous.