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Fiber Optics Illustrated Dictionary - Part 99

The Fiber Optics Illustrated Dictionary - Part 99 fills a gap in the literature by providing instructors, hobbyists, and top-level engineers with an accessible, current reference. From the author of the best-selling Telecommunications Illustrated Dictionary, this comprehensive reference includes fundamental physics, basic technical information for fiber splicing, installation, maintenance, and repair, and follow-up information for communications and other professionals using fiber optic components. Well-balanced, well-researched, and extensively cross-referenced, it also includes hundreds of photographs, charts, and diagrams that clarify the more complex ideas and put simpler ideas into their applications context | Fiber Optics Illustrated Dictionary ITU-T V Series Recommendations Number Description V21 A1984 dialup modem standard supporting data rates up to 300 bps. Most modems in the late 1970s and early 1980s were acoustical couplers with direct connect modems just beginning to catch on in the mid-1980s. V.22 A 1988 dialup modem standard supporting data rates up to 1200 bps with fallback to 600 bps. It is interesting to note that in the 1980s many technical people insisted it was impossible to support speeds faster than 1200 bps over standard phone lines and that this was probably the fastest speed at which modems would ever transmit data. V.22 bis A1988 update to the V.22 standard supporting data rates up to 2400 bps through frequency division techniques with link negotiation fallback to 1200 bps and fallback to V.22. V.23 Dialup modems supporting data rates up to 1200 bps with fallback to 600 bps and a 75-bps back channel or reverse channel. V.26 A1984 standard for modem supporting data rates up to 2400 bps on four-wire leased telephone lines. V.26 bis V.26 ter A1984 update to V.26 supporting 2400 and 1200 bps over public phone dialup lines. A1988 update to V.26 and V.26 bis that supports both echo cancellation public phone lines and point-to-point two-wire leased phone lines. V27 A 1988 standard for modem data rates up to 4800 bps with manual equalizer for use with leased telephone lines. V27bis A1984 update to V.27 that supports data rates of 4800 and 2400 bps with automatic equalizer for use with leased telephone lines. V27ter A1984 update to V.27 and V.27 bis that supports data rates of 4800 and 2400 bps over public phone dialup lines. V.29 V32 A1988 standard for modem data rates of9600 bps for four-wire leased telephone lines. A standard for public dialup and two-wire leased line modems with rates up to 9600 bps with fallback to 48 800 bps. This standard was approved in 1984. When modems incorporating V.32 were first introduced in the late 1980s it was not unusual .