Network uptime: what does it really mean?

Small differences in network uptime have huge impact on reliability

Network uptime is a critical focal point of any web hosting service. The majority of web hosting providers offer guaranteed uptime of 99.5% or more. But is that good enough? What about 99.9%? Or even 99.999%, which is sometimes called “five nines?” Seems like splitting hairs, and anything over 99% sounds great, right? But think again…

These seemingly minute differences in network uptime can actually have a huge impact on the reliability of your hosting service. In this article, we take a look at the differences in network uptime levels ranging from 99.5% to 100%.

Service level agreement

The service level agreement (SLA) is a section of the hosting contract that specifies the terms of service, including uptime. In the SLA, hosting providers will outline the amount of network uptime that they guarantee for the client’s chosen hosting plan.

Differences in network uptime percentages

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A few decimal places of uptime is the difference between nearly 9 hours of downtime per year at 99.9% to about 5 minutes per year at 99.999%. Considering that every minute a business site is offline can be measured in eroded customer dissatisfaction and lost revenue, can your business afford to work with a hosting provider that is only 99.9% reliable?

Why all hosting providers can’t offer 99.999% or 100% network uptime

network_uptimeProviding 100% or even “five nines” reliability requires technology, infrastructure redundancy, and expertise that most hosting companies just don’t have to offer. This level of reliability doesn’t happen by accident; it has to be designed into the hosting company’s business, and requires significant investment to achieve and maintain.

A hosting company’s SLA tells you how confident they are in their ability to deliver as promised. If a fast and reliable web site is mission-critical for your company, be sure to select a hosting provider that’s worthy of your confidence.