300,000 Phantom Smartphones Show Power of Network Model
On computer scientist John Floren's computer screen, thousands of green cartoon Android mascots crept around a map of Livermore, Calif. The screen resembled a map of Livermore Android users walking to lunch and otherwise moving through their day. However, all these "users" were virtual, controlled by software written by Floren and his colleagues that models how 300,000 smartphones would move and communicate in a city.
"We have this capability to spin off hundreds of thousands of Android virtual machines. We can give them simulated GPS locations," Floren told TechNewsDaily. "They can send text messages to each other."
Floren and his colleagues at Sandia National Laboratories in Livermore aim to make a freely available model of a city involving any number of smartphones, from hundreds to millions. App developers, government agencies and other groups could use the model to test their apps and email services, the Sandia scientists say. Researchers could use the model to understand how viruses spread between mobile devices. And the model could be the basis of something more sophisticated that shows how mobile networks would react to natural disasters, acts of terrorism and other emergencies.
For small startups, the virtual network would offer a taste of proprietary systems that are probably already being used by tech giants such as Google and Apple to test devices before they go to market, Floren said.
"We hope to make this into something where anyone with a desktop PC could run at least a couple hundred [virtual] Android machines," he said. Companies that want to run a model with more Androids would need to add more computers, he added. Sandia has a huge bank of servers for its model.
To mimic a Livermore full of Androids — an effort the Sandia scientists dubbed "MegaDroid" — researchers wrote several important smartphone capabilities into the virtual devices. Their model network is isolated from other networks at Sandia and from the outside networks, but each device in the model has "spoof" GPS locations that act as real GPS coordinates. The virtual smartphones are also able to send text messages to one another and appear to access the Internet.
These capabilities are enough to test location-based apps such as Foursquare, which lets users check into businesses they visit, Floren said.
For testing the effects of a cell tower going down in a disaster, researchers could add a model of cell networks, Floren said. For that, he and his colleagues would want to cooperate with another group that knows cell networks well.
The researchers plan to make a release-ready version of their so-called Mega projects over the next year. Besides MegaDroid, Floren and his colleagues have made virtual networks of Linux and Windows computers, projects they've named Megatux and MegaWin. They're also able to combine virtual Linux, Windows and Androids devices in one experiment.
Their long-term dream, which will take much longer than the next year, is a model of the Internet in a state or small nation. "We've always thought of the Mega thing as: Can we, in a cluster, model the Internet in a small state?" Floren said. "One of the advantages of being able to run all these different operating systems at the same time is that the more variety you have, the closer you get to modeling the Internet itself."