The analyst firm said the cost is likely to run into billions, as these figures do not take into account indirect costs such as loss of reputation or future sales.
The report, commissioned by managed service provider Worldport, said the main causes of Web site downtime are technical - failures of the power supply, network, physical infrastructure or lack of adequate security, and human - poor set-up and administration, monitoring or recovery planning.
These problems are magnified when Web sites are managed in-house, said the report's author Scott Smith, suggesting that companies should consider outsourcing Web site hosting. "External service providers are able to provide significantly higher levels of stability and redundancy," he said.
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