As today’s users can get access to the Internet anywhere and anytime, businesses receive hundreds and even up to thousands of user requests on their websites and applications every minute. This booming demand places substantial pressure on servers to keep up to serve users with high-quality content and media in a fast and reliable manner. Any downtime or interruption can result in poor user experience and lost revenues.

Load balancers have become an effective tool for service providers to handle this record-high level of application usage. What they do is spread traffic load across servers to avoid the incident of a single server being overloaded. So what are load balancers and how do they regulate incoming traffic to servers? Let’s find out in this article!

A load balancer is a physical device or software process in a server network that analyzes incoming user requests and spreads them across servers to make sure that no server is overloaded. Load balancers act as the traffic cop standing between client devices and backend infrastructure to route user requests in a manner that optimizes speed, stability, and capacity utilization.

When a server is down or reaches a traffic load ceiling, load balancers send new traffic to other servers in the network that are still online or have spare capacity.

Load balancers use a predefined pattern, often known as a load balancing algorithm or method, to regulate incoming traffic. Such an algorithm ensures that no single server has to handle more traffic than it is able to.

Here are how a load balancer basically works:

• A user sends a request on an application, and the application sends the request to the server.
• A load balancer receives the request and then routes that request to a certain server in the server farm by the preset pattern of the algorithm in use.
• The server receives the request and responds to the user via the load balancer.
• The load balancer receives the response and sends it to the user.

Massive traffic loads can overwhelm any single server, which can then cause disruptions in user experience and business processes. Load balancers are important because their relegating of incoming traffic helps ensure service availability during traffic spikes.

Load balancers also play a key role in scalability in cloud computing. As cloud users can scale up and down servers to accommodate their fluctuating computing needs, load balancers are what regulate traffic in these instances. Without load balancing, newly added servers wouldn’t receive incoming traffic in a coordinated manner or at all while existing servers became overloaded.

Load balancing algorithms can even identify if a server (or a set of servers) is likely to get overloaded to redirect traffic to other nodes that are deemed healthier. Such proactivity can minimize the chance of your application becoming unavailable.

There are two types of load balancers: hardware and software.

Hardware Load Balancers: Hardware load balancers are pieces of physical hardware that direct traffic to servers based on criteria such as the number of existing connections to a server, server performance, and processor utilization.

Software Load Balancers: Software load balancers are often easier to deploy than their hardware counterparts and also more flexible and cost-effective. Software load balancers give you the option to configure the load balancing to your application’s specific needs, but this comes at a cost which is more work required to set up your load balancer.

A load balancing algorithm is the logic, a set of predefined rules, that a load balancer uses to route traffic among servers.

There are two primary approaches to load balancing:

• Dynamic load balancing: Uses algorithms that distribute traffic based on the current state of each server.
• Static load balancing: Distributes traffic without taking the state of servers into consideration.

Some common dynamic load balancing algorithms are:

• Least connection: Directs traffic to the server with the fewest connections.
• Weighted least connection: Allows assigning different weights to servers, assuming some can handle more requests than others.
• Weighted response time: Routes traffic based on response time and the number of requests each server is serving.
• Resource-based: Distributes traffic based on available server resources like CPU and memory.

Some common static load balancing algorithms are:

• Round robin: Routes requests in a cyclical order across servers.
• Weighted round robin: Assigns different weights to servers and routes traffic accordingly.
• IP hash: Routes traffic based on the hash value of the source and destination IP addresses.

We hope that this article has provided you with valuable knowledge about load balancers in cloud computing. No organizations want to deal with server overload, and load balancers are an effective tool that can help them avoid this problem.

If your company doesn’t have the expertise to execute your cloud migration project in-house, it’s best to find a good cloud migration service provider to help you.