The Tripitaka Koreana, a complete collection of Buddhist literature, was created based on Buddhist patriotism, which at the time of its creation focused on defeating the Mongolian army through the power Buddhism. It is the oldest existing collection in the world, and its content and system are also considered to have reached the level of perfection.
The Tripitaka Koreana is made of high quality wood which was soaked in sea water and dried multiple times in order to protect it from decomposition. The building was also established on higher ground with great air circulation, so that it would be least affected by earthquakes.
Data centers in the 21st century are similar to the Tripitaka Koreana, because they also need to safeguard large amounts of data. Since data centers are supposed to be available for free access and data transactions around the clock, keeping and maintaining them is even more important.
Today, let’s have a look at the key safety elements that data centers have, and methods to protect them from earthquakes.
The most important part of a data center is the storage unit where data is saved. Data storage should follow multiple criteria to prevent data loss, and the three most important criteria are as follows.
① Low-exothermic Structure
The data storage unit in a data center exchanges data constantly, as it’s connected to the internet around the clock. The process causes great exothermic reaction, and the excessive heat can damage drives or even the CPU if not taken care of efficiently. To prevent this from happening, data centers require an effective air-conditioning system.
② Low Humidity
High humidity is often the main cause of electronic damage. Just like other electronics, drives used for data storage also contain lots of metal components. When the humidity level rises, these metal components can become rusty.
Corrosion then causes errors during data transaction, and the damaged drive needs to be either replaced of fixed. This is why it’s important for data centers to include equipment which keeps humidity levels low.
③ Consistent Power Supply
Data centers cannot have a single second of power shortage. Because data storage units constantly exchange data, even a short moment without power can cause data loss or damage. To prevent this problem, data centers are designed to either store emergency power or have their own generators to keep them running during power failures.
As you see, a lot of thought goes into protecting data. When hit by natural disasters such as earthquakes, however, these general measures cannot guarantee that data will be safeguarded anymore.
When building a data center, one more thing that must be considered is the geographical element and therefore the risk of earthquakes, floods, and volcanic eruptions must be measured. Volcanic eruptions and earthquakes are more common around volcanic and earthquake belts. Therefore, it’s better to build data centers on higher ground and away from ocean ridges.
Even though many people had believed that it was safe from earthquakes, Korea has recently experienced multiple incidents. And according to those regions where quakes occurred, even areas remote from ocean ridges can no longer be taken as perfectly safe locations. It’s important to understand that earthquakes can happen anywhere so that data centers can be prepared for these situations.
The biggest problem a data center may face in an earthquake is a loss of data. Earthquakes vibrate buildings, and the data storage inside vibrates with them. The vibration can cause physical damage to drives, and these damages can lead to data loss.
Other than physical damages to drives caused by vibration, there are also risks of short circuits and fire, which can cause interruptions to power supplies. Data exchange failures during these interruptions can lead to data loss.
Needless to say, what’s most important for a data center is the enormous amount of data it holds. As more people are becoming interested in big data, the important data kept in these centers is even more crucial. Saving faultless data is the key purpose of a data center. Then how can data centers remain safe from earthquakes?
Uptime Institute Inc. is an American organization which evaluates the stability of data centers based on a number of criteria. This institute evaluates the design and implementation of data centers and classifies them from tier 1 to 4.
The criteria not only check how data centers control power supplies and heads, but also contain a natural disaster risk category. The criterion for seismic elements in this category is based on Peak Ground Acceleration (PGA).
PGA is a figure that expresses the actual seismic force for vibration-proof designing. The figure is considered when designing vibration-proof buildings, so they won’t be damaged when an actual earthquake occurs.
There are three different types of vibration-proof design.
① Vibration-resistant Design
Vibration-resistant design keeps a building from collapsing when there is a horizontal vibration, by strengthening the building’s internal horizontal axis and minimizing impacts. This method is usually applied to low-rise buildings and can withstand up to 6.0 on the Richter scale.
② Vibration Control Design
Vibration control design means establishing equipment which applies a force opposite from the vibration caused by an earthquake to minimize the impact.
③ Vibration Isolation Design
Vibration isolation design inserts rubber or bearing equipment between the bottom of the building and the ground to minimize the direct impact from the ground during earthquakes. This method is usually applied to high-rise buildings and effective for up to 7.0 on the Richter scale.
LG CNS Cloud Data Center in Busan is the first data center in Korea to implement both vibration-resistant and vibration isolation designs to keep the building from vibrating.
Vibration-resistant design, which is the oldest method, only strengthens the horizontal axis to prevent collapse, so it’s not effective enough for high-rise buildings. By combining vibration isolation and vibration-resistant designs, the structure can minimize seismic impacts.
The cheapest design to implement is vibration-resistant design, whereas vibration control and isolation designs require relatively high cost. Yet these two are more effective ways to be prepared for earthquakes, so it’s better to combine all of them for a building’s safety.
Like libraries, data centers which store all the data created online need to constantly save and read data, while providing data and making meaningful records to make our lives more convenient.
Earthquakes are powerful enough to physically destroy buildings so designs to minimize or absorb their impact are among the key elements to consider when making a data center.
Data centers must be able to keep data safe for a long period of time. By implementing a thorough vibration-proof design, data centers will be able to safeguard all their records of this era.
Written by Woonje Sung, LG CNS Student Reporter