rencing systems buyers guide, 303 NT-1s controlling upgrades costs, 304 as they vary in price, 202 performance testing, 305 NTSC, 81, 458 personal conferencing technology Nx384, 458 application of, 303 Nyquist's Theorem, 92 personal conferencing usage model, 289 Nyquist's Theorum, 458 personal conferencing, specifications Oakley, 317,435 development, 141 omnidirectional microphones, 273 Peter Mark Roget, 80 P-frame on-line directories, 307 optical disk drives, 459 predictive coding, for MPEG, 341 ordering digital service phosphor, 462 ESF/B8ZS, 194 photorealism, 259, 375 organizational objectives, 55 phreaker, 311 OSI Reference Model, 170 physical interfaces to the videoconferencing network, 278 out-of-band signaling, 198 picture resolution, 104, 277 packet, 460 Picture-In-Picture, 462 packet switching, 460 Picturephone, 6, 9, 15, 296, 331, 462 packet-switched networks PictureTel, 9, 51, 245 transaction-oriented data, 223 C-2000 codec, 244 PAL, 85, 112 early videoconferencing system, 9 Palm os, 326 founding and early history, 244 Index Hierarchical Vector Quantization (HVQ Protocol-Independent Multicast (PIM), 185 algorithm, 244 PTT, 464 Motion Compensated Transform (MCT) public room, 464 algorithm, 244 Public Switched Telephone Network (PSTN), PictureTel Corporation, 243 public utility commissions (PUCs), 191 how it works, 186 push-to-talk microphones, 274 pixel, 462 Px64, 113, 245 plain old telephone service (POTS), 8, 462 Q.920, 464 point-to-point videoconferences, 4 Q.921, 464 Polycom, 20, 30, 37, 39, 147, 152, 243, 245, Q.931, 464 H channels, 207, 464 Polycom, Inc., 147 QCIF, 464 Post Telephone and Telegraph organizations (PTTs), 336 quadrature modulation, 84 post-Deregulation Act, 194 quantizing, 93, 465 prediction Quarter Common Intermediate Format (QCIF), 114 in motion compensation, 462 QuickTime, 465 Predictive Service (RSVP), 180 radio prioritizing videoconferencing room usage, origins of term, 68 private facilities Radio Act of 1927, 72 renting out excess capacity, 270 Radio Corporation of America (RCA