What is a Load Balancer?
When distribution of workload across multiple computers is done to achieve better performance, the process is called load balancing and is mainly driven by a load balancer. Load balancing happens in a way that no resource should experience overload to ensure that better performance is maintained. As a load balancer balances application requests across multiple servers, each server is prevented from flunking. Hence, application responsiveness and availability are enhanced.In other words, a load balancer ensures that all other servers in the pool are ready to catch the work that one server fails to perform. When there is an increase in application demand, new servers can be easily added to the resource pool and the load balancer is able to instantly start sending traffic to the available server. With this process, network traffic, database queries, and SSL requests are expected to be load balanced.While load balancing can be achieved with the help of software, the process is more often accomplished through the help of dedicated hardware appliance because of the speed requirements. Nonetheless, different algorithms can be used by a load balancer and one of them is round-robin. Being the most commonly used algorithm, round-robin is when a request is sent to each server in the cluster consecutively. At the same time, there are more complicated strategies that make decision according to the degree of CPU usage, the average response time, the number of queued requests, or the number of packets lost. However, problems arise when session of a particular user is not duplicated across the whole server cluster which makes the routing of the requests unsuccessful.Anycast is also a known method of load balancing which happens when a strategy which is usually being used in the DNS, where hosts in multiple geographical locations representing a similar IP address is applied. The load balancing happens as the requests are routed to the closest servers/hosts. When the closest host is unavailable, the request is immediately forwarded to the next closest available host. This process basically enhances response time and reliability.Load balancing is considered a good strategy because every task gets performed in a more efficient manner as resources are not overused which results to a better response time. But most of all, load balancing is ideal because normal functions can be maintained in spite of the server interruptions and failures caused by equipment malfunctions. In other words, failover is the best reason why load balancing is something worth applying. The latter and load balancing itself are powerful enough to allow network administrators to have some peace of mind while users continue their work.Load balancers play a very vital role in the process. As a matter of fact, load balancers have become very important in modern networks and the technology has even managed to provide more powerful solutions usually dubbed application delivery controllers. Moreover, these controllers cover advanced functionality like the SSL offload, content catching, TCP connection management, HTTP compression, monitoring of application performance and URL rewriting. The rise of cloud computing together with the development of mobile devices will absolutely feed the new generation of load balancers.
