"Part of what we do for carriers is minimize the traffic on their networks," Afergan says, adding that Akamai's servers also reduce DNS traffic.
The impact of social-networking sites is primarily on carrier and university networks today, but it is likely to affect more corporations as they add social-networking features to their e-commerce and intranet sites.
IBM, for example, runs its own social network called BluePages, which allows employees to provide information about themselves to other employees.
Meanwhile, Coca-Cola this month is set to launch a mobile phone-based social-networking community for Sprite drinkers called Sprite Yard.
"Imagine when there are thousands of these sites," says Ken Silva, CSO of VeriSign. "Then they will be a more significant share of overall DNS queries."
Silva worries more about the impact on DNS from the migration of telephony and television services to the Internet than he does about social-networking sites.
"If one big telephony provider migrates to the Internet, they could bring millions of users and generate big chunks of bursty growth," he says.
VeriSign is in the midst of a three-year, $US100 million upgrade to its DNS infrastructure, which supports the .com and .net registries and two root servers. The upgrade will increase the company's DNS capacity tenfold.
"Planning for these things like social-networking sites and large infrastructure moving to IP is what this upgrade is all about," Silva adds.
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