NEWTON, MASS. — It's no secret that some employees misuse the Internet surfing on the job. While legal liability is perhaps the most costly potential issue – just one employee sharing offensive content can expose and seriously embarrass your company – the costs don't stop there. Productivity may suffer.

Perhaps less well known is that your network efficiency may be at risk if even a small number of users download bandwidth intensive files.

A 2000 survey by Vault.com found that 25 percent of employees spent one hour or more a day surfing sites unrelated to work, while 22 percent said they spent 30 minutes to an hour a day.

Distributors concerned about Internet misuse may want to check out Internet filtering software as an option. Some leading vendors that help companies control Internet use without disrupting their networks are FutureSoft, iPrism, Sentian, Surfcontrol, Websense, and X-Stop.

Vendors such as Sentian point out how non-essential Web content can quickly clog up your network. Controlling Internet use helps conserve bandwidth, which may have hidden costs such as when firms buy a wider "pipe" to handle increased bandwidth loads. This may be exacerbated by employees' use of streaming audio, video, MP3s and other downloads.

Some other ways vendors propose to help you save money include freeing up bandwidth for mission-critical needs; increasing the efficiency of bandwidth you already have; and putting off future bandwidth purchases.

In one case, managers at Gremada Industries, a worldwide supplier of remanufactured parts for OEMs, chose software with flexibility to screen for varied levels of Internet access across company departments. Network administrator Jeremy Johnson says that "shop floor computers are blocked completely by user group to all Internet access, while other departments have filtered access."

Johnson set up work groups to implement the filtering access levels at Gremada, and he says Sentian made it easier by providing a straightforward Windows installation wizard. The software also integrated with the existing Windows 2000 network protected by a Cisco PIX firewall.