How many nines are really needed?

Despite the hype around 99.999 per cent network uptime (generally referred to as “five-nines”), at least one industry observer says the common perception that businesses will fail without five-nines uptime is misleading.

According to Dan McLean, research manager, network support and integration, at Toronto-based IDC Canada, the average business probably doesn’t need five-nines uptime, and many can most likely get by on as low as 98 per cent uptime.

“Five-nines is almost portrayed as being a demand of everyday business and everyday circumstances, and five-nines is like a lot of IT concepts. It’s like security; not all applications or all businesses require the same level or degree of reliability,” said McLean.

As with security, five-nines is an issue of cost, he said. Achieving and maintaining five-nines reliability is a very expensive undertaking. For instance, if a company has a database of information needed for operation, the company isn’t going to fail if the database goes down more than 0.001 per cent of the time. E-mail is another application that will not make or break a business, so does not require five-nines reliability, he said.

“It’s an issue of doing that assessment and really understanding where it is that you need the reliability and to figure out what degree you need of reliability or availability within specific segments and specific applications of your IT environment,” McLean said.

Much of the discussion surrounding five-nines reliability eventually refers to e-commerce and the perceived need for very high availability. As the clich