Does AT&Ts Sponsored Data Plan violate net neutrality rules?

On 6 January 2014, AT&T announced its Sponsored Data Plan at the Las Vegas Consumer Electronics Show. In short, the Plan ensures that subscribers to an AT&T dataplan for cellphones do not have to pay for accessing sponsored content or advertising through a 3G or 4G network; the advertiser pays for the capacity required to download the commercial content to the subscribers’ mobile phones. Politicians inWashington have already condemned AT&Ts initiative for reason that it would violate U.S. rules on net neutrality. AT&T has denied any relation between their Sponsored Data Plan and net neutrality principles.