Data Center Tiers

In this post we will talk about the different Tiers that exist in a CPD. The objective is to know the concept of the Tier in a CPD, to know the different types that there are and their differences.

When designing a CPD, there are many factors that are taken into account, including regulations and legislation. A concept regulated by the ANSI / TIA-942 Telecommunications Infrastructure Standard for Data Centers is that of the Tier. The Tier is a rating system determined by reliability.

This certification was created in the early 1960s by the Uptime Institute, which is the body in charge of managing the different levels of the TIER standard today.

An important concept that also has to be understood with the Tier is redundancy. In this case, it refers to the protection of hardware or data that are of a critical nature and that are to be protected against possible failures that may affect continuous use.

The concept of Tier indicates the level of reliability of a CPD associated with four defined levels of reliability. The higher the Tier number, the greater availability and, in turn, the higher costs associated with its construction and time to create the CPD.

As explained above, a CPD can be classified into 4 different types of Tier according to its characteristics. Next we will see what a CPD needs to be classified like this.

• Tier I: It is a basic CPD, without characteristics or measures against unexpected failures. It has all the basic functionalities of a CPD and allows planned or unplanned outages.
• Tier II: This type of CPD already has redundant devices that allow it to withstand failures or unplanned interruptions. It already has a technical floor, a backup generator and some more advanced redundancy measure than the basic devices.
• Tier III: The main characteristic of having this Tier is redundancy in the power line. This allows maintenance and voltage drops without losing CPD availability. Devices must be able to be serviced without interrupting service. Most of these CPDs are built to be converted into the next Tier as the demand of the company increases.
• Tier IV: Maximum category of a CPD. You must allow the services to be always active supporting any type of failure. Power redundancy becomes simultaneous power to avoid wasting time in a possible failure.

In Spain, the first Tier IV CPD built was in 2012 by the company BBVA. This is located in Madrid and ensures two levels of redundancy to give maximum availability. It was the 4th in the world at the time of its construction.

Later, Telefónica built its own, being the largest in the country in 2013. It has an area of ​​more than 65,000 square meters, equivalent to 8 football fields full of computer infrastructure and electrical components for the operation of this large CPD.

As we have seen, a CPD can be classified into 4 different levels according to its Tier, but this is not all. This classification is based on the TIA-942 standard and therefore the classification is valid if we are looking at this particular TIA. There are many ways to classify a CPD but this is one of the most recognized as the fault tolerance and availability of the CPD are the most important factors when building or designing a CPD.

Posted by Roger Marcen