The document discusses data center tiers as defined by the Uptime Institute. There are four tiers that classify data centers based on infrastructure and downtime. Tier 1 has the lowest availability at 99.67% uptime. Tier 2 improves on Tier 1 with redundant components. Tier 3 is concurrently maintainable with 99.98% uptime. Tier 4 is fault tolerant with 99.995% uptime and fully redundant power and cooling. The appropriate tier depends on a company's business needs and tolerance for downtime.

1. Data Center Tiers: Behind
the numbers

2. When you hear about TIERS in data center industry what
comes to your mind? Type, level, uptime, downtime or
infrastructure? Yes, Tiers in data center industry refers to
the operations of data center developed by the uptime
institute. This tier of classification is necessary while
choosing data centers as it provides methods to compare
and find the uniqueness and customized facilities based on
uptime or site infrastructure.
There are four accepted data center tiers rankings from the
uptime institute.
Tiers are TIER 1, TIER 2, TIER 3 and TIER 4 each tier shows
uptime and availability.

3. Tier one has basic capacity in which there is a 99.67% of
uptime and downtime of 28.8 hours downtime annually. In
Tier one data center dedicated site infrastructure is
provided to support IT beyond an office setting. It also
includes dedicated space for IT systems in which there are
engine generators are available to protect IT functions, a
UPS to filter power spikes, sags, and momentary outages
and dedicated cooling equipment. Tier 2 data centers have
redundant capacity components with an uptime of 99.75%,
and downtime of 22 hours annually.
Tier 2 includes all tier 1 capabilities but also add redundant
critical power and cooling component. Tier 2 redundant
components include UPS modules, chillers or pumps and
engine generators.

4. Tier 3 data centers are concurrently maintainable with an
uptime of 99.98% and annual downtime of 1.6 hours. Tier 3
data center includes capabilities of tier 1 and 2 data centers.
There are no shutdowns while replacement and
maintenance of equipment. Tier 3 data centers are not
faulted tolerant as they share different components as
external cooling and utility company feeds. It contains
redundant cooling systems where if one cooling unit
shutdowns the other one kicks and continue the cooling
systems. The tier 4 Datacenter have all the capabilities of
one, two and three tier data centers. The Tier four data
centers are fault tolerant. Power and cooling components
are 2N fully redundant which refers to IT components are
doubled where there are two different cooling systems, two
generators, two UPS systems. Tier 4 Datacenter has
99.995% of uptime and downtime of only 0.4 hours.

5. However, it is important to know the business needs for
these tiers before choosing a data center. Tier 1 and 2 can
work well for small-scale companies which don’t need 24x7
availability as they can survive for days for maintenance.
In this type of cases, you don’t need to opt for 3 and 4 tiers
data centers. In multinational companies where business is
round the clock and several critical application running can
which can’t afford downtime should opt for data center
which is 3 or 4 tier compliant.
Further Information Contact:
Web Werks Data Centers
www.webwerks.in