A recent survey shows that network managers worry how voice could affect their data applications, and that worry could hinder their plans to roll out VoIP.

Network General, maker of Sniffer Voice and other network management tools, conducted the survey of 100 network managers with research firm Enterprise Management Associates and found the perceived or potential performance impact of voice applications was a primary inhibitor to full-scale enterprise deployments of VoIP.

Nearly 60% of respondents are already using VoIP as their primary voice communication system, and about 50% have been using VoIP for more than a year. But according to the survey results, nearly half of IT managers surveyed discovered that "both VoIP and data applications were impacting each other, resulting in degradation of overall network performance."

Jim Vale, Network General’s product manager for Sniffer Voice, says the fear of performance degradation has many survey respondents keeping their voice deployments smaller than if data network performance had not been affected.

"We found that the majority of North American companies polled were doing something with voice, and of that, many are doing it in limited deployments," he says. He says the concern over performance could be why more than two-thirds of IT managers used performance network capacity planning tools, upgraded bandwidth links, and installed network and VoIP monitoring tools prior to their VoIP rollouts.

In fact, 51% of respondents said they found VoIP management tools to be critical, while 39% found them very important. Only 10% said VoIP management products were somewhat important. Also, the survey found that 77% of respondents were using their current network and application management tools to address the new voice applications.

Another noteworthy item, according to Network General, is that 6% of managers believe that tools to manage voice and data must overlap, in the case that one person or group is responsible for both network and voice application performance.

"The overlap indicates to us that the telephony team will need to know how to manage data and vice versa," Vale says.

Ann Bednarz is associate news editor at Network World.