84 infrared emitting diode, 12 security, 79, 80 injection laser diode, 12 testing, 71 node, 100 Jackfield, 69, 70 Optical fiber, 90, 91 Keyboard, 53 optical mark reader, 66 Laser printer, 60 Packet assembler, 101 leased line, 93 packet operation, 102 line analyzer, 76 packet switching, 98 line costs, 14 packet switching services, 115 line driver, 114 PAD, 101 link control procedure, 33 parallel transmission, 4 local area network, 86 parity, 45 logical channel, 101 double, 46 logical matrix, 105 spiral, 47 loop check, 48 vertical, 46 loop topology, 83 patch panel, 69 phase shift keying, 17 Master/Slave topology, 83 PIN photodiode, 12 message switching, 93, 94 polling, 43 Modem, 7, 16, 17 printer, 56 applications, 19 band, 59 features, 20 daisywheel, 57 voiceband, 19 impact, 57 wideband, 19 line, 59 Modulation, 17 matrix, 58 FAX, 64 protected field, 54 FSK, 17, 24 protocol, 32 multilevel, 6, 9 comparison, 42 PSK, 17 hierarchy, 32 QAM, 18 public data network, 96 INDEX 131 Quadrature amplitude modulation, 18 synchronous, 8 SYNC charactrer, 28 Raster graphics, 62 read coding, 66 TDMA, 110 telex, 115 redundancy, 70, 106 terminal considerations, 54 repeaters, 6 test equipment, specialized, 75 ring topology, 83 RS449 interface, 20 testers, portable, 75 RS232C interface, 20, 34 time division multiplexing, 27, 28, 29 token passing topology, 83 topology, 82 Satellite, 107 traffic statistics, 104 channel, 107 transponder, 107 structure, 110 trouble tickets, 74 systems, 110 trunk testing, 74 scanning, 29 twisted pair, 91 scrolling, 54 TWX, 115 SDLC, 41 serial transmission, 4 Uplink, 109 simplex, 5 single mode fiber, 11 Vertical distribution, 92 SNA, 42 VF patching, 69 star configuration, 82 virtual call, 99 statistical multiplexer, 25, 29 virtual circuit, 101 statistical network, 86 step index fiber, 11 WATS, 114 storage tube, 62 workstation, 67 stroke writing, 62 switching, 69 X.25 standard, 99, 100 WILEY Telecosmos The Next Great Telecom Revolution JOHN EDWARDS Telecosmos The Next Great Telecom Revolution John Edwards WILEY