Twice a year the IT industry starts buzzing about employees slacking off at work. The first flare-up is during the March Madness college basketball tournament, when early-round games are broadcast live over the Internet. Then comes the holiday season, when scores of shoppers use corporate time and resources to find gifts. But in reality, recreational traffic is a yearlong issue.

The latest vendor to tackle the problem is Exinda Networks, which added a new capability to detect and classify encrypted peer-to-peer (P2P) traffic to its WAN optimization and application acceleration wares (compare products). 

There are dedicated Internet filtering products that can block employee access to recreational sites and restrict traffic on certain ports, of course. But Exinda’s strategy is to integrate these capabilities into its traffic-management appliances. Its new classification engine is designed to help IT staff control a broad range of recreational Internet traffic, such as instant messaging, gaming and downloading files for entertainment.

Recreational P2P traffic goes largely undetected on corporate networks, yet is stealing bandwidth and slowing business applications, Exinda maintains. According to a survey conducted by Ashton, Metzler & Associates last year, use of recreational applications at work is widespread. About 63% of IT professionals reported seeing unauthorized use of company networks for IM, and 58% said they see unauthorized use for P2P file sharing.

These days, some of the biggest culprits that generate encrypted P2P network traffic are Skype, which offers telephony, file transfer and video capabilities; BitTorrent, which is used to download large files such as movies, TV shows and MP3 files; and social networking sites MySpace and Facebook.

For WAN optimization vendors, the challenge is how to properly handle encrypted P2P traffic, according to Con Nikolouzakis, Exinda’s CEO. Skype and BitTorrent traffic were designed to use different network ports and file server IP addresses, making it very difficult for firewalls to detect it.

“There are situations where encrypted peer-to-peer traffic is used for legitimate business purposes such as conference calls being hosted on Skype. In those instances, it is important to be able to detect and prioritize this traffic rather than restrict it,” Nikolouzakis said in a statement.

Ann Bednarz is associate news editor at Network World.