A battery-powered transmitter is all that would be needed to bring down the UK's 4G network, according to new research.

LTE Network Crashes

London's shiny new 4G network, which is only up and running for two weeks, could be brought crashing down using one simple trick.

New research has proved that using a piece of equipment costing not much more than £400could cause the high-speed LTE network to crash.

According to research findings provided to a federal agency in the US last week, the simple jamming technique using a battery-operated transmitter aimed at tiny portions of the LTE signal could knock out a large LTE base station, serving thousands of people.

Jeff Reed, director of the wireless research group at Virginia Tech, along with research assistant, Marc Lichtman, described the vulnerabilities in a filing made last Thursday to the National Telecommunications and Information Administration (NTIA), which advises the White House on telecom and information policy.

"Picture a jammer that fits in a small briefcase that takes out miles of LTE signals-whether commercial or public safety," Reed told the MIT Technology Review.  "This can be relatively easy to do," and it would not be easy to defend against, Reed added.

The NTIA asked for submission on the possibility of using a 4G LTE network as the basis for a new communications system for emergency response services. This is in response to the communication problems suffered after the 9/11 terrorist attacks, which added to the death toll.

Terrorists

Reed's submission stated terrorists could use the vulnerability in LTE networks to their advantage:

"If LTE technology is to be used for the air interface of the public safety network, then we should consider the types of jamming attacks that could occur five or ten years from now. It is very possible for radio jamming to accompany a terrorist attack, for the purpose of preventing communications and increasing destruction."

Any radio frequency can be blocked or jammed if a transmitter sends a signal at the same frequency, with enough power.

The researchers found that LTE was not vulnerable to just one type of attack, but to eight:

"There are multiple weak spots-about eight different attacks are possible. The LTE signal is very complex, made up of many subsystems, and in each case, if you take out one subsystem, you take out the entire base station," Lichtman said.

Laptop

Anyone who wanted to take out some part of an LTE network, such as EE's 4G network currently operating in 11 cities around the UK, would only need a laptop and an inexpensive "software-defined radio unit."

Not much power would be need to carry out this attack either, with a car battery enough to bring down some portion of an LTE network. However some expert knowledge would be required by the attackers, according to Lichtman:  "Any communications engineer would be able to figure this stuff out,"

With LTE networks rolling out around the world, and Ericsson estimating that half the world's population will have LTE coverage by 2017, this vulnerability could be a significant problem.

Qualcomm, which is one of the leading providers of LTE chipsets to the like of Samsung and Apple, has refused to comment on the situation so far.