Load Balancing

Cloud load balancing refers to distributing client requests across multiple application servers that are running in a cloud environment. Like other forms of load balancing, cloud load balancing enables you to maximize application performance and reliability; its advantages over traditional load balancing of on‑premises resources are the (usually) lower cost and the ease of scaling the application up or down to match demand.

An ever‑growing number of companies – especially small businesses – are running applications of all sorts in the cloud. A company might use a cloud‑based CRM such as Salesforce.com to store customer information, a cloud‑based ERP system to track product data, a web‑hosting vendor like Google to host its website, and Amazon Elastic Compute Cloud (EC2) to run a handful of custom applications. It’s considered best practice to provision the load balancer server in the same environment as the resources it is load balancing. So when most of a company’s computing infrastructure is hosted in the cloud, it makes sense to run the load balancer in the cloud too.

Hardware vs. Software Load Balancing
Traditional load balancing solutions rely on proprietary hardware housed in a data center, and require a team of sophisticated IT personnel to install, tune, and maintain the system. Only large companies with big IT budgets can reap the benefits of improved performance and reliability. In the age of cloud computing, hardware‑based solutions have another serious drawback: they do not support cloud load balancing, because cloud infrastructure vendors typically do not allow customer or proprietary hardware in their environment.

Fortunately, software‑based load balancers can deliver the performance and reliability benefits of hardware‑based solutions at a much lower cost. Because they run on commodity hardware, they are affordable even for smaller companies. And they are ideal for cloud load balancing, as they can run in the cloud like any other software application.

Benefits of Cloud Load Balancing
The benefits of cloud load balancing in particular arise from the scalable and global character of the cloud itself.

The ease and speed of scaling in the cloud means that companies can handle traffic spikes (like those on Cyber Monday) without degraded performance by placing a cloud load balancer in front of a group of application instances, which can quickly autoscale in reaction to the level of demand.

The ability to host an application at multiple cloud hubs around the world can boost reliability. If a power outage hits the northeastern U.S. after a snowstorm, for example, the cloud load balancer can direct traffic away from cloud resources hosted there to resources hosted in other parts of the country.