­The USA's Federal Trade Commission is challenging the public to create an innovative solution that will block illegal commercial robocalls on landlines and mobile phones.

A commercial robocall is a telephone call that delivers a recorded sales message. These calls often are unwanted and frequently deceptive. Under the FTC's Telemarketing Sales Rule, the vast majority of commercial robocalls are illegal unless the recipient has given the caller advance written permission to call them.

As part of its ongoing campaign against these illegal, prerecorded telemarketing calls, the agency is launching the FTC Robocall Challenge, and offering a $50,000 cash prize for the best technical solution.

This is the agency's first government contest hosted on Challenge.gov, an online challenge platform administered by the U.S. General Services Administration, in partnership with ChallengePost.

"The FTC is attacking illegal robocalls on all fronts, and one of the things that we can do as a government agency is to tap into the genius and technical expertise among the public," said David Vladeck, Director of the FTC's Bureau of Consumer Protection, when he announced the challenge and prize this afternoon at the Commission's Robocall Summit. "We think this will be an effective approach in the case of robocalls because the winner of our challenge will become a national hero."