In a business continuity survey of 7,000 CDW customers, 1,794, or about 25%, reported experiencing a network disruption of four hours or more within the last year.
CDW then conducted a second poll of 200 IT decision-maker customers who had experienced significant network outages since July 2009 and found that half said power loss was the top cause of the problem. Hardware failures were cited by 29% of the respondents and lost telecommunications were named by 21%.
CDW polled customers for its Business Continuity Straw Poll, which looks at how businesses dealt with disruptions and the measures they're taking to improve business continuity and disaster recovery capabilities.
Ninety-seven percent of those surveyed said the network disruptions had "detrimental effects" on business productivity.
"The survey confirms that while many businesses believe they are prepared for an unplanned network disruption, many are not - and yet the three most common causes of IT outages are addressable," Norm Lillis, vice president of CDW system solutions, said in a statement.
Lillis said that with more preparation, testing and improved network accessibility, most of the businesses could have avoided an outage or responded more quickly when one occurred.
The survey also showed that 53% of the businesses surveyed allow employees to work from home when a foreseeable disruption, such as during a hurricane, is imminent. However, only a third of respondents activate standby communications and network systems to support increased remote access when warned of an impending event.
While 44% of respondents said their workforce has telecommuting options, only 39% of their employees could take advantage of that option during the network outage, the survey showed.
The survey results also showed:
- 51% experienced problems connecting to their IT network from other locations.
- 50% had problems connecting from inside their business locations.
- 46% said employees could not access the necessary company resources to do their jobs during an outage.
Of the 200 respondents who a significant outage in the past year, 34% said they are moving to update business continuity and disaster recovery capabilities, CDW said.
"No two network disruptions are the samem" Lillis said. "It is great to see businesses strengthening their plans, and there is always room for improvement. It is critical that businesses test their infrastructure and [business continuity] plans at least once a year, to pinpoint weaknesses before it is too late."
Lucas Mearian covers storage, disaster recovery and business continuity, financial services infrastructure and health care IT for Computerworld. Follow Lucas on Twitter at @lucasmearian or subscribe to Lucas's RSS feed . His e-mail address is lmearian@computerworld.com.