50 Parallel searching, 22 Numerical Aperture (NA), 114 system design and Parallel transmission, 32-34 Nyquist formula, 35-36 implementation, 206-211 Parity checks, 88-89 Nyquist sampling theorem, 11-13 Optical fibers, 111 Parity codes, 91 NZDSF. See Nonzero Dispersion- cross-phase modulation, 139 Passive Optical Networks Shifted Fibers dispersion, 118-120 (PONs), 153 four-wave mixing, 142-143 Path loss in free space, 238 future evolution, 143-144 PATH message, 390-391, 394 OAM. See Operations, losses, 115-118 Path Overhead (POH) bytes, 314, Administration, and multimode fibers, 120-127 318-319 Maintenance nonlinear optical effects, 133 contiguous concatenation, 346 OAM&P. See Operations, optical waveguides, 111 SDH, 319 Administration, SBS, 138-139 virtual concatenation, 350-351 Management, and self-phase modulation effects, virtual containers, 325-326 Provisioning capabilities 136-138 Payload FC Indicator (PFI) bit, OCs. See Optical Carriers single-mode fibers, 127-133 Odd-integer harmonics, 31-32 special, 133-136 Payload size in SDH, 327-330 Odd parity, 88 SRS, 139-141 Payload Type Identifier (PTI) ODUs. See Optical Data Units structure and physics, 111-115 field, 357 OFDM. See Orthogonal Optical Transport Network PBBs. See Provider Backbone Frequency Division (OTN), 420 Bridges Multiplex modulator Ordered LSP control, 389, 391 PBB-TE. See Provider Backbone Offset reflectors, 295-296 Ordinary waves, 248 Bridging with Traffic Omnidirectional antennas, 277 Orientation angle in polarization, Engineering On-demand binding, 389 PBT. See Provider Backbone On-Off Keying (OOK), 39 Orthogonal Frequency Division Transport One-time pads, 103 Multiplex (OFDM) PCD. See Polarization-Dependent Open-loop systems, 291 modulators, 106 Chromatic Dispersion Index PCM. See Pulse Code Modulation POH bytes. See Path Overhead Preamplifiers PCT. See Paired Comparison Test bytes BER, 175-176 PDFs. See Positive-Dispersion Point of Presence (POP), 372 optical, 156 Fibers Point-to-multipoint Pre-emphasis in optical PDG. See Polarization-De