CAMBRIDGE, Mass, Feb 25 (Reuters) - The head of the U.S. Federal Communications Commission said on Monday he is "ready, willing and able" to stop broadband providers that unreasonably interfere with subscribers' access to Internet content.

The comment by FCC Chairman Kevin Martin came at the start of a day-long FCC hearing centering on allegations that some broadband providers such as telecommunications and cable companies have been improperly blocking or hindering some content.

"I think it's important to understand that the commission is ready, willing and able to step in if necessary to correct any (unreasonable) practices that are ongoing today," Martin said.

The dispute over so-called "network neutrality" pits open-Internet advocates against some service providers such as Comcast Corp, who say they need to take reasonable steps to manage traffic on their networks.

Martin acknowledged that broadband network operators have a legitimate need to manage the data flowing over their networks. But he said that "does not mean that they can arbitrarily block access to particular applications or services."

The hearing, which included testimony from officials with Comcast and Verizon, is aimed at determining what network management techniques are reasonable.

Martin called for "transparency" in the way the companies manage their networks, and in the prices and services they provide.

The network neutrality dispute has been spotlighted by a series of incidents in which operators were accused of hindering certain online data moving over their networks, such as file-sharing or text-messaging.

The issue also has attracted the attention of lawmakers in Congress, who are weighing a net-neutrality bill introduced last week.

In the most recent example, the FCC has been looking into complaints by consumer groups that Comcast has blocked some file-sharing services which are used to distribute large digital media files such as TV shows and movies.

In comments filed with the FCC, Comcast told regulators that it uses reasonable measures to manage traffic moving over its network, as some of its customers overwhelm the network by using file-sharing applications like BitTorrent.

Comcast, which is the second-largest U.S. Internet service provider with more than 13 million subscribers, said the use of network management was essential to avoid congestion and impairment of some applications. The company denied that it blocks content, applications or discriminates among providers.

Internet service providers are looking at different ways of managing the increasing amount of traffic moving across their networks both for cost management and for quality of service reasons.

Critics have argued that imposing network neutrality regulations on the Internet would hinder development of the Internet by creating uncertainty for investors and Internet service providers. (Reporting by Svea Herbst-Bayliss in Cambridge and Peter Kaplan in Washington; editing by Tim Dobbyn)

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