Wireless.A.to.Z Nathan.J.Muller McGraw.Hill 2003

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.The Federal Communications Commission(FCC) approves mergers with input from the Department ofJustice (DoJ).In the case of the SBC-Ameritech merger, theFCC imposed 28 conditions on SBC in exchange for approv-ing the transaction.The approval package contained a sweeping array of con-ditions designed to make SBC-Ameritech s markets themost open in the nation, boosting local competition by pro-viding competitors with the nation s steepest discounts forresold local service and full access to operating support sys-tems (OSS).It also required SBC to accelerate by 6 months its entryinto new markets, forcing the company to compete in 30 newmarkets within 30 months after completion of the merger.The FCC s rationale was that increased competition in out-of-region territories would help offset reduced competition inthe SBC-Ameritech service areas.INCUMBENT LOCAL EXCHANGE CARRIERS 163The conditions also required stringent performance moni-toring, reporting, and enforcement provisions that could trig-ger more than $2 billion in fines if these goals were not met.Fortunately for SBC, the agreement required it to serve onlythree customers in each out-of-region market.According toSBC, it will not begin to seriously market its out-of-region ser-vices until it has obtained approval to offer long-distance ser-vices in its 13 home states.SummaryThe monopoly status of the ILECs officially ended with pas-sage of the Telecommunications Act of 1996.Not only canother types of carriers enter the market for local services incompetition with them, but also their regional parent com-panies can compete in each other s territories.Throughmergers, the reasoning went, the combined companies canenter out-of-region markets on a broad scale quickly and effi-ciently enough to become effective national competitors.Unfortunately, this has not occurred on a significantscale.In fact, the lack of out-of-region competition amongthe Baby Bells means that consumers and businesses donot have as much choice in service providers, especiallynow that many Competitive Local Exchange Carriers(CLECs) are being hit hard by financial problems and thelack of venture capital.The ILECs are more concerned withbeing able to qualify for long-distance services in their ownmarkets so that they can bundle local and long-distanceservices and Internet access a package few, if any, com-petitors would be able to match.See alsoCompetitive Local Exchange CarriersInterexchange CarriersLocal Exchange Carriers164 INFRARED NETWORKINGINFRARED NETWORKINGINFRARED NETWORKINGInfrared (IR) technology is used to implement wireless localarea networks (LANs) as well as the wireless interface toconnect laptops and other portable machines to the desktopcomputer equipped with an IR transceiver.IR LANs are pro-prietary in nature, so users must rely on a single vendor forall the equipment.However, the IR interface for connectingportable devices with the desktop computer is standardizedby the Infrared Data Association (IrDA).Infrared LANsIR LANs typically use the wavelength band between 780 and950 nanometers (nm).This is due primarily to the readyavailability of inexpensive, reliable system components.There are two categories of IR systems that are commonlyused for wireless LANs.One is directed IR, which uses avery narrow laser beam to transmit data over one to threemiles.This approach may be used for connecting LANs indifferent buildings.Although transmissions over laser beamare virtually immune to electromechanical interference andwould be extremely difficult to intercept, such systems arenot widely used because their performance can be impairedby atmospheric conditions, which can vary daily.Sucheffects as absorption, scattering, and shimmer can reducethe amount of light energy that is picked up by the receiver,causing the data to be lost or corrupted.The other category is nondirected IR, which uses a lessfocused approach.Instead of a narrow beam to convey thesignal, the light energy is spread out and bounced off nar-rowly defined target areas or larger surfaces such as officewalls and ceilings.Nondirected IR links may be further categorized as eitherline of sight or diffuse (Figure I-1) [ Pobierz całość w formacie PDF ]

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