Today, while load balancing is still in use, it is now only considered a feature of Application Delivery Controllers (ADC). As load balancers evolved from DNS round-robin routing, ADCs have evolved from the first load balancers. They are considered to be the next generation load balancer. They tend to offer more advanced features such as content manipulation, advanced routing strategies as well as highly configurable server health monitoring. They also tend to offer features like compression, cache, connection multiplexing, application layer security, SSL offload and content switching combined with basic server load balancing.

ADCs have evolved from the realization that simply being able to reach an application doesn’t necessarily make the application usable with performance enhancement being the most obvious extension. One of the first extensions included SSL/TLS offload where dedicated servers performed this function reducing the heavy amount of computational overhead required of the encrypted traffic on the back-end servers.

Another example is the application of compression technology. The overhead of compression and decompression adds latency that increased throughput may not make up for from a performance perspective, particularly in the cases involving short physical distances and large bandwidth. Therefore the ability to intelligently apply compression when it will provide the most gain gives benefits to end-users and resource (processing availability) utilization alike.

As the evolution of ADCs continue, the start-up needs to carefully consider when and how their implementation will benefit the performance, reliability and scalability of the company’s application.