What is Load Balancing? How Load Balancing Works

When bringing content across the internet, there are various processes involved that most users are unaware of. The content you access comes from a server, which takes a lot of processing to deliver the right content to you. This is where load balancing comes in!

When a website starts receiving more traffic than usual, it tends to slow down, which can disrupt user experience. In order to keep the website up and running, web developers employ load-balancing techniques. In this article, we’ll go through the various types and benefits of load balancing and how it works to keep your site engaged with users.

What Is Load Balancing?

The process of effectively dividing incoming network traffic among a collection of backend servers also called a server farm or server pool, is called load balancing. The method is used to speed up everything for every end user by decreasing response time, raising throughput, and generally increasing the speed of your website.

With the ever-growing use of technology, modern websites are integrating this technique since they have to deal with high volumes of traffic on a daily basis. In order to guarantee that all resource servers are used equally, a load balancer is a device positioned between the user and the server group.

Types Of Load Balancers

The use of each type of load balancer depends on the network’s needs. There are the following two types of load balancers:

Hardware Load Balancers

A hardware load balancer is a hardware device that can safely process and reroute enormous amounts of data to hundreds of distinct servers. Data centers hold these, and you can utilize virtualization to make several load balancers that are digital or virtual, which you can control centrally.

Software Load Balancers

Applications that handle all aspects of load balancing are known as software-based load balancers. They utilize online virtual machines or white box servers to run as an application delivery controller. They can be accessed as a fully managed third-party service or installed on any dedicated hosting server. Virtual load balancing offers high flexibility and enables users to scale up or down as needed according to the network activity.

Benefits of Load Balancing

Load balancing is responsible for directing and controlling internet traffic between the visitors and the application servers. This helps improve the overall website experience. Some key benefits of load balancing the network traffic are as follows:

Performance

Load balancers enhance application performance by speeding up application response times and cutting down on network latency. They evenly distribute the load among servers to enhance the performance of your application.

Additionally, you can cut down on latency and reroute client requests to a server that is closer to them geographically with the help of this technique. Lastly, verifying the efficiency and dependability of both physical and virtual computing resources becomes possible with the use of load balancers.

Security

Your internet applications will benefit from an additional layer of protection thanks to the built-in security capabilities of load balancers. When an attacker overwhelms an application server with millions of simultaneous requests, causing server failure, they can utilize them as a helpful weapon to counteract distributed denial of service assaults.

Moreover, load balancers can keep an eye on traffic and remove harmful information. They can automatically reroute attack traffic to many backend servers to reduce effect. What’s more astonishing is that the traffic directs through a collection of network firewalls for further protection.

Scalability

Websites or applications are scalable by directing network traffic across multiple servers with the use of a load balancer. Your application can handle thousands of requests at a time while load balancing prevents traffic bottlenecks from occurring at any one server.

It also helps with predictive analysis so that you can add or remove different servers according to the needs of your application traffic. Moreover, you get redundancy for your system, which helps you scale easily.

Improved Uptime

Server failure or maintenance increases the application downtime, leaving your program inaccessible to users. By rerouting client traffic to available servers and automatically identifying server issues, load balancers improve the fault tolerance of your systems.

With the use of load balancing, you can redirect network traffic to another high-performance dedicated server while one of them goes under maintenance or upgrades. This way, you keep your website up and running without any downtime. It also helps with automatic disaster recovery to easily backup sites.

Load Balancing Algorithms

The collection of guidelines that a load balancer uses to choose the optimal server for each type of client request is a load-balancing algorithm. There are two major types of load-balancing algorithms.

Static Load Balancing

This type of load-balancing algorithm follows fixed rules and is independent of the current server state. Some examples of static load balancing are:

• Round-Robin Method: IP addresses on servers indicate to clients where to submit requests. The IP address is a lengthy, hard-to-remember number. Rather than using specialized hardware or software for load balancing, the round-robin technique uses an authoritative name server. The name server returns the IP addresses of each server in the server farm either in a round-robin or turn-by-turn manner.
• Weighted Round-Robin Method: In this type of load balancing, you get to dedicate each server with a different weight based on their capacity or priority. The name server will send more application traffic to any server with a higher weight than the others.
• IP Hash Method: In this method, a mathematical computation known as hashing is performed by the load balancer on the client’s IP address. After the calculation, the client’s IP address converts to a number for mapping on individual servers.

Dynamic Load Balancing

This type of load balancing depends on the current state of the server. In fact, it checks the current state of the servers before distributing traffic. Some examples of dynamic load balancing are:

• Least Connection Method: A communication channel between the client and the server is called a connection. When a server receives any requests from the client, it establishes an active connection between them. In this method, the load balancer checks the server with the fewest active connections and sends traffic to those ones, ensuring that all connections require equal processing power for all servers.
• Weighted Least Connection Method: Certain servers are able to manage more active connections than others via weighted least connection methods. As a result, you may give each server a different weight or capacity. The load balancer then routes incoming client requests to the server with the fewest connections based on capacity.
• Least Response Time Method: The amount of time the server needs to process incoming requests and provide a response is known as the response time. The optimal server is the one using the least response time technique, which combines the server response time and the number of active connections. Load balancers use this method to guarantee quicker service for all users.
• Resource-Based Method: Load balancers use the resource-based approach to distribute traffic by examining the server load at any given time. Each server has specialized software called an agent that monitors how much memory and processing power are being used by the machine. The load balancer then distributes traffic to that server after verifying with the agent that there are enough free resources available.

How Load Balancer Works?

Mostly, businesses operate their application over several servers. A server farm is a configuration of servers like this. The user request routes through the load balancer to the application first. Each request then passes by the load balancer to the one server in the server farm that has the ability to handle it efficiently.

A load balancer acts as a reverse proxy. It presents a virtual IP address on VPS to represent the application to the client. After the client establishes a connection with the virtual IP, the load balancer uses its algorithms to determine which application instance on the server should get the connection. The load balancer then monitors the connection until it’s in process.

Types Of Load Balancing

Load balancing has four main categories, depending on how it redirects the traffic of client requests.

Application Load Balancing

Many server farms with numerous servers devoted to a single application function are part of complex contemporary applications. To reroute traffic, application load balancers examine the content of the request, such as HTTP headers or SSL session IDs.

Network Load Balancing

In order to properly divert traffic, network load balancers look up IP addresses and other network information. They are able to identify the application traffic’s origin and provide many servers with static IP addresses. Network load balancers employ static and dynamic load balancing techniques to balance server load.

Global Server Load Balancing

The process of global server load balancing involves several geographically dispersed servers. If a business has servers in several data center hosts across borders and with third-party cloud providers worldwide, local load balancers will control the application load inside a zone or area. They try to reroute traffic to a server destination that is closer to the client’s location. If a server fails, they may only reroute traffic to servers outside of the client’s geographic area.

DNS Load Balancing

You set up your domain name to distribute network requests across several resources on your domain when you use DNS load balancing. A website, mail server, print server, or any other internet-based service can all be associated with a domain. Maintaining application availability and distributing network traffic among a globally dispersed pool of resources are two benefits of DNS load balancing.

Conclusion

Choosing the algorithm and type of load balancing depends on the requirements of your business application. Optimizing website performance and ensuring a seamless user experience is crucial in modern times.

By efficiently distributing network traffic among multiple servers, you can get more engagement and increase your brand awareness. Using hardware and software load balancers, coupled with various load-balancing algorithms, enhances application performance, improves security against cyber threats, facilitates scalability, and minimizes downtime.

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