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What is data center extension?

Data center extension is a technique that involves integrating an on-premises data center with a public cloud infrastructure in order to leverage the public cloud’s elasticity and scalability. In other words, it’s an application of a hybrid cloud infrastructure that allows a business to seamlessly migrate virtual machines and workloads in and out of the cloud. 

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Some common use cases for data center extension include:

  • Footprint expansion: Businesses that want to expand the capacity of their data center or move into new geographic areas can extend their data centers to the cloud instead of building a new on-premises data center.
  • Temporary traffic spikes: Data center extension allows a business to scale up its capacity for short-lived or periodic traffic spikes without having to make a larger, permanent investment in an on-premises infrastructure capable of handling the maximum volume of traffic at all times. 
  • Test and development environments: Instead of continually creating and destroying test environments in the data center, businesses can move these workloads to the public cloud to reduce strain on on-premises resources.
  • Hybrid applications: Extending the data center to the cloud allows businesses to develop and deploy applications that can integrate with on-premises applications as well as access cloud-native services.



How does data center extension work?

Data center extension works by establishing connectivity between the on-premises data center and the cloud environment, either through the Internet, through a VPN or through a private connection option such as AWS Direct Connect. This allows seamless integration between the data center and the cloud, allowing IT to provision workloads to either the data center or the cloud, or to spin up extra instances of an application in the cloud at times when there is increased traffic (a practice known as “bursting” to the cloud).



Advantages and disadvantages of data center extension

Because data center extension leverages public cloud architectures, it offers many of the same benefits as cloud itself, including:

  • Improved performance and agility
  • Scalability and elasticity
  • Cost savings


However, data center extension does have one potential disadvantage: Depending on the vendor you choose, it can be difficult to implement. This can be a result of the following factors:

  • Difficulty matching up architectures between on-premises and cloud environments
  • The need to rearchitect legacy applications for public cloud
  • Incompatible technology stacks (including hypervisor, networking and storage)


By performing a data center extension assessment to carefully consider your needs and take your current infrastructure into account, you can avoid these difficulties and effectively integrate your data center with a cloud-based data center extension.



How to use the cloud to extend your data center

Before undertaking a data center extension, it’s important to think about your needs (such as connectivity, capacity and cost) and your goals for the data center extension. Consider whether you need to perform live migration of workloads into and out of the cloud, for example, and whether you need to migrate workloads without changing their IP addresses. Why are you planning to extend your data center, and what do you hope to achieve by doing so?


Once you’ve outlined your needs and goals, you can a choose a service that meets those needs. It’s also a good idea to use a service that’s based on the same underlying technology that you use in your on-premises data center, so that your IT team is already familiar with the technology.



Will the cloud replace the data center?

Technically, the cloud can’t replace data centers completely. After all, the cloud itself still runs on physical data centers somewhere. But when most people say “data center,” they’re referring to an on-premises data center, and by this definition, there is indeed a strong trend toward increasing adoption of cloud infrastructure. In one survey, 73 percent of respondents reported that the cloud would be their primary deployment venue for a majority of workloads in 2020. However, security and compliance considerations make it unlikely that the cloud will ever completely replace the on-premises data center. For organizations that have strict compliance requirements or want to make the most of their existing investments in their data center infrastructure, leveraging the cloud as a data center extension offers the flexibility of cloud with the security and control of an on-premises data center.



Does the cloud need data centers?

Since cloud computing runs on data centers, the cloud itself does need data centers. But an organization running its workloads on a public cloud doesn’t need to build and maintain its own data center—it can simply use the offsite data centers provided by the cloud provider. However, some organizations may still prefer to maintain an on-premises component to their hybrid cloud architecture. This could include organizations that have already invested in an on-premises data center, that have special security or compliance requirements, or that simply prefer the control and customization that a data center provides.



What are the biggest expenses in running a data center?

There are many costs involved in setting up and maintaining an on-premises data center. Some of the biggest expenses include: 


  • Hardware and facilities costs: An on-premises data center requires not only an investment in expensive hardware, but also facility space to store that hardware, electricity to run it and systems to cool it. 
  • Maintenance: All that hardware takes labor to maintain, test and upgrade.
  • Staff and training: Facilities, IT and security staff must be trained on data center operations and then paid to staff the data center.


These costs can be reduced or minimized by balancing use of an on-premises data center with public cloud services.



What are the 3 biggest trends currently impacting the data center?

The data center is evolving, and new trends and technologies are allowing businesses to take advantage of innovative architectures and techniques, including data center extension. Here are three of the biggest trends affecting how businesses use their data centers:


  1. Software-defined data centers (SDDCs): Businesses are increasingly adopting this data center model, in which compute, storage and networking are virtualized so that they can be managed and provisioned flexibly and easily. With the right solution, an SDDC can easily integrate with public cloud services for effective data center extension.
  2. Cloud adoption: Although the cloud may never fully replace the on-premises data center, more and more businesses are turning to cloud-based architectures, products and services. This increase in adoption is changing how businesses think about and use their data centers. 
  3. Hybrid cloud and multi-cloud: When choosing a cloud solution, rather than migrating everything to the public cloud, many businesses turn to hybrid cloud or multi-cloud solutions. These allow them to take advantage of the scalability and flexibility of public cloud while also maintaining an on-premises data center and the security and control it provides.


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