Much of Japan was left without internet access Friday after a Google data error misdirected the internet's routing system.

Popular banking and gambling sites were among the affected sites.

The interruption was brief, reportedly lasting less than an hour, but the Japan Times reports that it was enough to spur Japanese government officials to demand telecommunications companies provide reports on the internet. The Times credits the outage for boosting stocks related to network security, including SecuAvail Inc., whose price jumped by 10 percent.

ADVERTISEMENT

The problem stemmed from the border gateway protocol (BGP), a cooperative system that networks together smaller networks to make up the internet. Most smaller networks do not connect directly to one another, and the BGP helps each network determine what path through the smaller networks will best get data from one point to another.

The smaller networks self-report how far away they are from one another. Google, which does not transport other data across its network, accidentally "leaked" its routing table to the Japanese internet provider NTT, making it appear that Google was a massive shortcut to far off networks.

But Google does not transport data in this way, so all the data sent to it was lost.

BGP routing errors have periodically had broad impacts, including a 2010 incident where as much as 15 percent of the world's internet traffic was redirected through China.