IT managers are losing control of the applications running over their networks, according to a new survey.

More than half of 100 network managers said they believe that a significant portion (40% or more) of their network bandwidth is being consumed by recreational or non-business-critical applications, but they confessed to lacking granular visibility into the applications running across their networks. In addition, 50% of respondents believe that IT knows about 60% or less of the actual applications being run on the network.

That’s a lot of unknowns.

The survey was commissioned by Blue Coat Systems and conducted in the U.K. But I can’t imagine the conditions are confined to Britain. Around the world, users’ recreational apps consume corporate network resources. Just how much bandwidth is used for recreational traffic can be tough to quantify if you don’t have the right tools.

In particular, one reason for the lack of visibility into applications running on the network is the growing use of SOA and Web 2.0 technologies such as mash-ups. These technologies make it more difficult to determine the nature of application traffic on the network and whether the content is harmful, according to 56% of respondents.

A big increase in malicious Web threats also has had a detrimental impact on networks, say 85% of respondents.

Lastly, the sheer volume of applications makes it hard to maintain adequate visibility; 51% of respondents say the number of applications employees have in use on the corporate network has risen by 200% or more over the last two years.

“The findings show that there is huge potential for organizations to save money, improve security and get better application response times by getting a better handle on what network traffic is running on the network,” said Nigel Hawthorn, vice president of international marketing and channels at Blue Coat, in a statement.

Of course, Blue Coat has a stake in the situation; its ProxySG appliances combine security features to block malicious content with acceleration features to prioritize and accelerate business-critical applications. For application visibility, Blue Coat offers its PacketShaper appliances (gained in last year's acquisition of Packeteer), which can classify more than 600 applications and monitor more than 100 application attributes.

Ann Bednarz is associate news editor at Network World.