A four tier system that provides a simple and effective means for identifying different data center site infrastructure design topologies. The Uptime Institute's tiered classification system is an industry standard approach to site infrastructure functionality addresses common benchmarking standard needs. The four tiers, as classified by The Uptime Institute include the following:

If you are concerned about security, data protection, and working with a viable and stable company, then Tier 4 is a must. Look around and you'll soon
find that there are few hosting companies in this category.
Tier IV data centers have all the bells and whistles; everything needed to keep them running without ever shutting down for maintenance, no matter what happens.
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