Voice -- 1 percent-3 percent

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Carriers in Chaos

The commoditization of voice services is putting pressure on carriers that provide key parts of global enterprise networks. Facing competition from cable companies as well as VOIP start-ups like Vonage Holdings Corp. and Skype Technologies SA, telecommunications companies foresee a rapid and potentially destabilizing decline in voice revenues.

The uncertainties are creating a great deal of disruption in the market, says David Passmore, an analyst at Burton Group. "Who would have thought that AT&T and MCI would disappear?" he says of the recent mergers with SBC Communications and Verizon Communications, respectively. Yet the changes so far could be mere ripples compared with the turbulence that lies ahead. Voice service revenues could disappear if, as expected, Internet service providers bundle unlimited VOIP calling as just another subscriber feature.