 standards, 74 criticality of, 73 MAC (Media Access Control) addresses in, 72 Layer 2 Tunneling Protocol (L2TP), 241, 242 Layer 3 switches, 121 criticality of, 73 IP addresses in, 71 redundancy, 74 Layer 4 switches, 121 layers, OSI (Open Systems Interconnection), 41-42, 65 LC (Little Connector), 14 LEDs (Light-Emitting Diodes), 17 legacy systems, 187, 200-201 legislation. See regulatory issues LEO (low earth orbiting) satellites, 381 Level 3 Communications, 134, 152, 195 Library of Things, 316 Lifeline subsidies, 127, 142-143 Light-Emitting Diodes (LEDs), 17 light-source transducers, 17 www.TechnicalPDF.com Limelight, 195 Linc VoIP, 233 LinkedIn, 52, 163 Little Connector (LC), 14 load balancing, 120 lobbying, 147-148 Local Access And Transport (LATA) areas.168 local area networks. See LANs (local area networks) local channels, 254 Loews, 36 Long-Term Evolution. See LTE (Long-Term Evolution) networks loss, packet, 102 low earth orbiting (LEO) satellites, 381 LTE (Long-Term Evolution) networks, 335-339 4G LTE, 336-337 architecture, 341-342 capacity, 338 cell site functionality, 338 customer connections, 349-350 evolved packet core databases, 343-344 frequency-division air interfaces, 355-356 HetNets (Heterogeneous Networks) characteristics of, 351 DAS (Distributed Antenna Systems), 354 definition of, 350 equipment in, 352 femtocells, 353-354 pico cells, 353-354 history of, 335 IMS (IP Multimedia Subsystem), 347-348 IP Core, 343-344 MIMO (Multiple-Input Multiple-Output) antennas, 356-357, 359, 370-371 www.TechnicalPDF.com OFDM (Orthogonal Frequency-Division Multiplexing), 357-358 time-division air interfaces, 355-356 types of, 358-359 VoLTE (Voice over LTE), 345-347 M2M (machine-to-machine) mobile services, 367 MAC (Media Access Control) addresses, 72 machine learning, 5, 22-23 macro cells, 351-352 magicJack, 233 managed services, 235. See also MPLS (Multi-Protocolo Label Switching) advantages of, 245 definition of, 245 typical offerings, 246-247 MANO (Management and Organization), 179-181 MANs (Metropolitan Area Ne