The fatter the pipes, the higher the usage, and now, it appears, the bigger the potential for malware too.

At least that's what a new study from Alcatel-Lucent (NYSE: ALU)'s Kindsight Security Labs has concluded. The security division discovered that mobile malware infections rose 20% last year, with 4G LTE devices most often infected. Of those, Android is still the most vulnerable.

Devices with Google (Nasdaq: GOOG)'s operating system on board accounted for 60% of the infections, typically in the form of trojanized applications downloaded from third-party app stores, Google Play Store, or by phishing scams.

This is the same proportion that Kindsight found when it released its report last quarter. At that time less than 1% -- 0.6% -- of devices had been infected; this quarter it was even smaller at 0.55%, or 11.6 million mostly Android devices, infected with malware. (See Android's Still a Malware Magnet.)

The number isn't high enough for grave concern. As Heavy Reading analyst Patrick Donegan pointed out with last quarter's report, the industry should even be applauded for the 99.4% of devices that aren't infected. (See LTE Brings Myriad Security Concerns.)

It's long been known that LTE is more susceptible to threats than 3G. It's an all IP network, so it adopts the vulnerabilities of both a fixed and mobile network. But, Kindsight says it's also simply because LTE networks are used more than their 3G predecessors. As JDSU (Nasdaq: JDSU; Toronto: JDU)'s study last week pointed out, LTE users tend to download more data and spend more time on the mobile Internet. (See LT-Extreme: 4G Subs Use 10X More Data and Mobile Data Trends in Developing & Developed Markets.)

"On average, an LTE user consumes twice as much data, including 50% more video, than 3G users," says Mark Hudson, director of communications for Alcatel-Lucent's IP platforms group. "Simply put, LTE devices are more likely to get infected simply because they are more actively surfing the Internet."

As a vendor that sells network-based security services, Alcatel-Lucent's conclusion is hardly surprising: Operators need more network-based security services. But whether it comes from them or not, it's certainly true that security has to start in the network. (See Network Security in a 4G LTE World.)

In other news from the department of shameless plugs, Heavy Reading's Donegan will be hosting a breakfast on this very subject, "Creating Trust in the Mobile Network," at Mobile World Congress on February 26. Find out more and register for the breakfast here. (See Coffee, Tea, or Network Security?.)

— Sarah Reedy, Senior Editor, Light Reading