Does your small business offer Internet access to customers? If so, you should get proactive about security.

The National Federation of Independent Businesses has issued an urgent warning to small business owners: take steps to prevent customers from logging on and illegally downloading copyrighted materials.

Why the urgent alert? Because copyright holders—including record labels and movie studios—struck a deal with Internet Service Providers to issue warnings to residential customers whose accounts are allegedly used to pirate content.

Although the agreement doesn’t impact commercial businesses, small businesses could be affected, according to the NFIB. Small businesses that have residential accounts for Internet connections could meet with “mitigation measures” if the provider sniffs out illegal activity five times.  Those measures could include reducing Internet speeds or redirecting traffic to a special landing page until the customer contacts the Internet provider to discuss the issue.

“This could potentially be an issue for home-based businesses or small businesses whose owners are using residential accounts for whatever reason,” says Beth Milito, senior executive counsel for NFIB. "Regardless, it’s a good idea for small businesses to take precautions to prevent customers or even employees from using their Internet connection to steal content."

Milito says requiring a password is a simple way to discourage abuse: "For example, they could print a password on the receipt and change it periodically, to prevent non-customers from using the service."

Businesses can also block access to certain websites and types of websites, Milito suggests: "This requires a little bit of know-how on the part of the small-business owner, and it may accidentally block access to legitimate websites, but it also can discourage people from using a business' network to steal content. With more and more people carrying smartphones and even tablets, free Wi-Fi can help a small business attract and keep customers, but unless a business owner uses commonsense and takes precautions, those customers could come at a hefty price.”

Check out this video for more Wi-Fi security tips: