WDTalk

Five nines or 99.999% relates to - the up time availability of data centers. Prospective clients look for uninterruptable uptime as a prerequisite to constitute reliability of a data center, but what is acceptable to one may be inadequate to another. Accordingly, this expectation of uptime relates to a demand for computer reliability. Data center infrastuctures include a variety of critical physical layer environmental sub-systems that must integrate cohesively. Among those are power and cooling. If a system is deemed ‘fault tolerant,” this means it can sustain a worst case, unplanned event and NOT disrupt the end user.

The Four Tiers of Data Centers

Tier 1

It has non-redundant capacity components and single non-redundant path distribution paths serving the site’s computer equipment.

Tier 2

A tier 2 data center has redundant capacity components and single non-redundant distribution paths serving the site’s computer equipment.

Tier 3

A tier 3 data center has redundant capacity components and multiple distribution paths serving the site’s computer equipment.

Tier 4

This is a fault tolerant data center with redundant capacity systems and multiple distribution paths simultaneously serving the site’s computer equipment.

A tier rating for an entire site is limited to the rating of the weakest subsystem that will impact their operations.