Hello,

We noticed you're browsing in private or incognito mode.

To continue reading this article, please exit incognito mode or log in.

Not an Insider? Subscribe now for unlimited access to online articles.

Tom Simonite

A View from Tom Simonite

A Crowdfunding Campaign to Set Smartphones Free From Cellular Networks

The Serval project begins raising funds for a device to help smartphones connect without a cellular network

  • July 11, 2013

The Serval project, whose free software can enable smartphones to make calls and send messages without a cellular network, is appealing for help developing a home router-like device that could make its novel approach more practical. A crowdfunding campaign aims to raise $300,000 to support development of the Mesh Extender, as it is called, which helps the ad-hoc, localized networks Serval creates to extend over larger distances. Potentially just as important, the device also makes it possible for nearby phones to join a mesh network without being modified to sidestep default restrictions on Wi-Fi networking in Google’s mobile operating system. The current prototype is pictured at left in the image above, while the Serval project’s founder, Paul Gardner-Stephen, holds a mockup of a more refined version.

The prototype shown at left can enable nearby Android phones to link up for calls, texts, and file transfers without a cellular network. (Credit: Serval Project)

The free app for Android phones developed by Serval has nearby phones link up to one another using Wi-Fi, creating a “mesh” network in which every device can act as a stepping stone to help data travel between any other (see “Build Your Own Internet”). Such networks could be very valuable in places with poor infrastructure, after a disaster, or in face of government surveillance. But a phone can’t make a Wi-Fi connection longer than about 100 meters with a clear line of sight, and such a link can typically only reach an adjacent building in an urban area.

The Mesh Extender the new campaign is raising funds for can make both local Wi-Fi links and links several kilometers long, thanks to an additional radio that uses a part of spectrum typically frequented by cordless phones and garage door openers. Once turned on, a Mesh Extender can link nearby phones into a mesh network via Wi-Fi, and then connect those devices to any others linked to any other Mesh Extenders within range of its second radio. The current Mesh Extender design can be legally used in the U.S., Canada, Australia, and New Zealand. Prototypes have been tested in places as varied as the Australian outback and the National Mall in Washington, D.C. The new campaign will fund development of a more refined version that could be sold online, and for early units to be sent to humanitarian organisations for testing in the kind if environments Serval is designed to help out in.

Another feature of the Mesh Extender that may be more of interest to some is that it allows Android devices to join a Serval mesh network over Wi-Fi without being modified, or “rooted,” to turn off default restrictions on that type of Wi-Fi networking. Buying and switching on just one Mesh Extender could allow a school, hacker club, or other group to easily experiment with mesh networking.

Become an MIT Technology Review Insider for in-depth analysis and unparalleled perspective.

Subscribe today

Uh oh–you've read all of your free articles for this month.

Insider Premium
$179.95/yr US PRICE

Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus the digital magazine, extensive archive, ad-free web experience, and discounts to partner offerings and MIT Technology Review events.

    See details+

    What's Included

    Unlimited 24/7 access to MIT Technology Review’s website

    The Download: our daily newsletter of what's important in technology and innovation

    Bimonthly print magazine (6 issues per year)

    Bimonthly digital/PDF edition

    Access to the magazine PDF archive—thousands of articles going back to 1899 at your fingertips

    Special interest publications

    Discount to MIT Technology Review events

    Special discounts to select partner offerings

    Ad-free web experience

/
You've read all of your free articles this month. This is your last free article this month. You've read of free articles this month. or  for unlimited online access.