Increasingly popular social-networking sites such as MySpace, YouTube and Facebook are accounting for such huge volumes of DNS queries and bandwidth consumption that carriers, universities and corporations are scrambling to keep pace.

The trend is prompting some network operators to upgrade their DNS systems, while others are blocking the sites altogether. Moreover, the "MySpace Effect" is expected to hit many more nets soon, as these network-intensive interactive features migrate from specialty sites to mainstream e-commerce operations and intranets.

"Social media is not just going to be in pure-play sites like MySpace and Facebook. It's going to become increasingly prevalent across retailers, media and entertainment," says Mike Afergan, CTO of Akamai, a content delivery network company that supports MySpace, Facebook and Friendster. "It drives a lot more requests and a lot more bit-traffic across these networks."

The demanding nature of social-networking sites was highlighted in May when the Department of Defense announced it was blocking worldwide access to 13 Web sites, including MySpace and YouTube.

"The Commander of DoD's Joint Task Force, Global Network Operations has noted a significant increase in use of DoD network resources tied up by individuals visiting certain recreational Internet sites," Army General B.B. Bell said in a memo. "This recreational traffic impacts our official DoD network and bandwidth availability, while posing a significant operational security challenge."