Skip to content Skip to navigation Skip to footer

What is a Data Center?

A data center is a centralized physical facility that stores businesses’ critical applications and data. A common data center definition is a location where computing and networking equipment is used to collect, process, and store data, as well as to distribute and enable access to resources.

The Growing Role of Data

The electronic exchange of data is now required for nearly every business and personal interaction. Even traditional tasks such as making a phone call, reading a book, or watching TV are now largely digital. This ever-growing demand for digital information requires vast amounts of computing and networking equipment, which are stored in data centers.

Data centers have existed since the early days of computers but have evolved dramatically as technology becomes cheaper, smaller, and more advanced. The early data centers were typically comprised of one huge supercomputer, but modern versions are now home to thousands of servers connecting to various communication networks. 

This shift is largely being driven by an exponential growth in data volumes. For example, IDC’s Data Age paper predicted a tenfold increase in data levels between 2018 and 2025. It predicts 175 zettabytes of data will be in existence by 2025 which, if you attempted to download at the current average internet speed, would take 1.8 billion years to download.

This mass of data now connects across multiple data centers, at the edge, and on public and private clouds. But it still has to be stored somewhere. So the modern data center remains as crucial as ever. However, it has to evolve to communicate across on-premises facilities, various cloud locations, and cloud providers. As a result, the modern data center infrastructure has developed from on-premises physical servers to virtual infrastructures that support applications and workloads in multi-cloud environments.

Given the importance of the vast amounts of data businesses now have, as well as the applications and server resources they power, data centers now have dedicated data center firewalls to protect them.

Components of a Data Center

Servers and IT Equipment

The essential components of any data center often include cybersecurity systems, firewalls, routers, servers, storage systems, and switches.

A core commonality of all data centers is servers. A data center server is a high-performance computer that is packed with a lot more memory. It is vastly faster and a more powerful processor. A server or group of servers may be dedicated to a single task, multiple applications, or a specific client.

Storage devices, such as hard-disk, solid-state, and robotic tape drives are important to helping any data center run these servers.  Another vital component is networking and communication equipment, which is necessary to maintain a high-bandwidth network between servers. This is comprised of routers, switches, network interface controllers, and endless miles of cables that help information to flow through the data center.

In addition to this hardware, data centers rely on software to run it. This includes various operating systems and applications that run on their servers, clustering framework software like MapReduce or Hadoop, and virtualization software to reduce the number of physical servers.

Facility Systems

At physical locations, data center rooms require security systems to prevent unauthorized access. They are typically protected by alarms, biometric scanners, gates, security doors, and security staff. The site will have emergency equipment like fire alarms, sprinklers, and safety measures to protect data center against the noise of the servers, fans, and more.

In addition to security, data centers rely on energy-efficiency systems and equipment that keeps the facility running smoothly. This includes power equipment like backup batteries and generators and uninterruptible power supplies. Cooling systems and equipment to handle air quality and temperatures, such as air handlers, chillers, fans, sensors, and water pipes and tanks, ensure servers run efficiently.

Data Center Tiers

The Uptime Institute, an advisory organization focused on improving the performance, efficiency, and reliability of business-critical infrastructure, defined four data center facility tier classifications. These tiers are recognized as the industry standards to follow for data center performance. Investing in this certification process helps data centers to prove compliance and demonstrate their expertise in facility management to customers.

The four data center tiers are as follows:

The Four Data Center Tiers Data Center Tiers

Tier 1: Basic Capacity

A Tier 1 data center provides the basic capacity level required to support IT for an office. It requires an uninterruptible power supply (UPS) for power outages, sags, and spikes, an area for IT systems, dedicated cooling equipment that runs outside office hours, and an engine generator for power outages.

A Tier 1 facility protects against human error but offers limited protection against unexpected failures or outages, and will have to shut down completely for repairs and maintenance. As a result, it provides 99.671% uptime, no redundancy, and will experience 28.8 hours of downtime per year.

Tier 2: Redundant Capacity

Tier 2 data centers offer improved protection against physical events. They provide maintenance and safety against disruptions through equipment like cooling systems, energy generators and storage, fuel tanks, and pumps. Like a Tier I facility, an unexpected shutdown affects the system, resulting in 99.749% uptime and 22 hours of downtime per year.

Tier 3: Concurrently Maintainable

Unlike Tier 1 and 2 data centers, a Tier 3 facility does not need to be shut down when equipment maintenance or replacement is required. It features redundant components and distribution paths that ensure it is concurrently maintainable. 

A Tier 3 data center is more suited to larger businesses and will protect against most physical events. It offers 99.982% uptime, is N+1 fault tolerant to provide at least 72 hours of power outage protection, and experiences less than 1.6 hours of downtime per year.

Tier 4: Fault Tolerant

Tier 4 data centers feature independent, physically isolated systems that create redundant capacity components and distribution paths. This ensures that planned or unplanned disruptions will not affect the facility and IT operations. All IT equipment in a Tier 4 facility must have fault-tolerant power design, and the building requires continuous cooling so the environment remains stable.

A Tier 4 data center is typically suitable for enterprise corporations. It provides 99.995% uptime with just 26.3 minutes of annual downtime. It also offers 2N+1 fully redundant infrastructure and 96-hour power outage protection.

FortiNAC product demo request

Request a Product Demo

Request Demo

How Data Centers Operate

Data centers centralize organizations’ IT operations and equipment to ensure a secure location for storing, sharing, and managing vast amounts of data. They provide businesses with flexibility in how they back up and store their data, as well as protecting it from natural and man-made disasters. Data centers receive, store, and send data to support critical business applications and power data-intense services such as:

  1. Artificial intelligence, big data, and machine learning
  2. Data storage, backup, recovery, and management
  3. Ecommerce activity and transactions
  4. File sharing and email
  5. Real-time collaboration and productivity tools

The components of a data center require a vast infrastructure to support its hardware and software. This includes power and cooling equipment, as well as connections to external networks and security appliances such as firewalls and intrusion protection. Application performance is safeguarded by delivery assurance mechanisms that provide availability and resiliency through automatic failover and load balancing.

Types of Data Centers

There are various types of data centers that businesses can build or store their data within. These include:

Colocation Facilities

A colocation facility rents out space that is owned by the data center provider. The data center infrastructure is hosted by the building owner, which includes equipment and services for bandwidth, cooling systems, networking, power, and security. The company or service provider renting the space is responsible for installing and managing components such as firewalls, data center servers, and storage.


An enterprise data center is a facility that has been built by and is owned and operated by a business for its own use. The facility can be located in the organization’s own site but is typically situated off-premises at a location that offers prime connectivity, power, and security. Building and equipping an enterprise data center requires significant capital investment but enables organizations to design it to fit their specific requirements.

Hyperscale Data Centers

hyperscale data center is designed to provide the hyperscale computing that is necessary for cloud and big data storage. A hyperscale facility enables major cloud players to provide robust, scalable applications and storage services to their customers. These facilities are typically at least 10,000 square feet in size and have more than 500 cabinets and 5,000 servers running on an ultra-high-speed network. The key difference between hyperscale and enterprise data centers is the high fiber network that is utilized across a hyperscale facility. 

The Data Center and Your Business

As volumes of data multiply to exponential levels, the data center continues to play a pivotal role in daily operations for businesses of all sizes. It is more important than ever for organizations to have a tight handle on data as it helps them gain an advantage on their competitors, deliver optimal user experience, and ensure they comply with data regulations.

Businesses can choose to build and manage their own data centers, buy space within a colocation facility, use shared compute and storage services, or look to the public cloud. Or do a little bit of everything. The end result is still the same, as they remain reliant on the data center to support their applications and deploy their services to customers and users.

Whichever approach businesses choose, securing the data center is crucial. FortiGate is a data center firewall that secures enterprise data centers with next-generation firewall technology. Discover how Fortinet can help your organization protect the enterprise with data center firewalls.