xtensions), 109-110 Optical add/drop multiplexers (OADMs), 452, Orbits 463-464 GEO satellites, 66-67 Optical channel, OTN, 476 HALEs, 72 Optical cross-connects, 464 LEO satellites, 69-70 Optical line terminal (OLT), 526 MEO satellites, 69 Optical multiplex section, OTN, 476 unusable satellite altitudes, 69 Optical network units (ONUs), 527 VSATs, 67-69 Optical networking, 451-488. See also Fiber optics Orthogonal Frequency Division Multiple Access ASON, 487-488 (OFDMA), 574 bandwidth abundance for, 456 Orthogonal Frequency Division Multiplexing See drivers of, 452-453 OFDM (Orthogonal Frequency Division falling prices in, 452 Multiplexing) GMPLS, 485-487 Oscillation, 551 IP+optical control plane, 483-485 OSI (Open Systems Interconnection) reference model next-generation digital loop carriers, layers of, 166-168 471-473 VS. TCP/IP, 170-171 in next-generation networks, XXXV, 141, 411 OSPF (Open Shortest Path First) now VS. future, 453-456 IS-IS VS., 262 overlay model, 473-478, 483 as link-state routing protocol, 259-261 overview of, 451-452 for mesh networks, 655 peer-to-peer model, 473-474, 478-483 overview of, 260-261 switches, 92 OSS (operation support system), 697 UNI, 487 OTM (optical transport module), 476 Index OTN (Optical Transport Network), 475. See also Panel antennas, 556 Overlay networking model PANs (personal area networks), 149. See also Out-of-band signaling, 132-133 WPANs (wireless personal area networks) Outsourcing model, COPS, 445 PAP (Password Authentication Protocol), 286 Overlay networking model Parameters, ATM QoS, 439 ASON and ATSN, 476-478 Parity bits, 161 defining, 474-475 Parity checking, 162 overview of, 476 Passive communication mode, NFC, 684 peer-to-peer model VS., 483 Passive hubs, 188 Oxygen layer, and microwave, 55 Passive optical networks. See PONs (passive opti- cal networks) Passive RFID tags, 676-677 PABXs (private automatic branch exchanges), 7 Passive topology, 186 Packet headers, 93 Password Authentication Protocol (PAP), 286 Packet loss, 152, 216 Path loss, 554-555 Packet 