Attacks show fiber optic Internet cables vulnerable

More than a dozen physical attacks on the fiber optic Internet cables appear to be the work of vandals, not terrorists, experts and the FBI suggest.

Criminals have sliced fiber-optic cables that form the Internet's backbone in California at least 16 times in the past year, federal officials said.  The two newest attacks happened Monday night near Livermore, Calif. The FBI is unaware of any similar attacks elsewhere in the country.

"There's no physical evidence or intelligence to suggest a motive of terrorism," said Michele Ernst, a spokeswoman for the FBI's San Francisco office. "But we have not established a motive yet, so we are not ruling anything out."

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AT&T is offering a $250,000 reward in connection with the latest attacks. AT&T's fiber optic network is legally considered a critical piece of the nation's Internet infrastructure, and any attackers are subject to both state and federal prosecution. The FBI already has an open investigation into 14 similar attacks on California Internet backbones since last summer.

Livermore is a San Francisco Bay Area suburb that's home to the Lawrence Livermore National Laboratory and many high-tech commuters.

Security expert Richard Doherty of the New York-based Envisioneering said it's unlikely a terrorist or foreign government would repeatedly make low-level attacks that generally just inconvenience users. When the attacks first happened, some security experts suggested a foreign government could be launching the attacks as a probe to test the response and repair times in preparation for a much larger attack.

"If you're going to do an attack, you find a vulnerability and then shut up about it," Doherty said Wednesday. He called the cuts a "discoordinated" attack.

The repeated attacks show widespread vulnerabilities in the Internet's physical infrastructure.

The high-capacity lines, which aren't much thicker than a pencil, carry vast amounts of data. They act like interstates for the information superhighway Phone calls, computer transactions, emails, and even the security cameras feeds watching the cables themselves travel down plastic or glass fibers as pulses of light.

But the lines are easily severed. In some of the attacks, the FBI said, the culprit entered underground vaults and then sliced through a protective metal conduit to reach the cables.

While Internet traffic is automatically re-routed to avoid service interruptions, the attacks have, in some cases, cut off access for local users for hours. As with cars on the interstate facing a road closure, data traveling through internet backbones can take alternate routes. But the closer the data gets to the end of the road, the fewer options it has. Doherty said outages like these would likely disrupt some data transmissions, like Skype, but otherwise just slow access temporarily to online services, such as Facebook or Twitter. He said it's possible the cuts could also disrupt the transmission of critical medical or financial data.

Unlike military cables, which are constantly monitored by both equipment and soldiers, the private internet backbones are left largely unguarded, especially as they run for miles across remote sections of the country. The federal government considers the cables part of the nation's critical infrastructure, but leaves their management and protection up to their owners.

"We just don't do a very good job of protecting our critical infrastructure," Doherty said. "All of these things are wake up calls.