What is the primary protocol used for load balancers?

The primary protocol commonly associated with load balancers is TCP. Load balancers are designed to distribute network or application traffic across multiple servers, ensuring no single server becomes overwhelmed with too much traffic. While HTTP, which operates over TCP, is frequently used in web applications, the fundamental protocol that underpins most load balancing functions, including both web and non-web services, is TCP.

TCP is essential because it provides reliable, ordered, and error-checked delivery of data between applications. This reliability is crucial for maintaining consistent performance and user experience when handling large volumes of requests, which is a typical scenario in high-performance computing environments.

In contrast, HTTP is specifically tailored for web traffic and may not be used in situations that require load balancing for other types of applications. UDP can be used in some load balancing scenarios, particularly for services where speed is prioritized over reliability, but it does not provide the same level of error checking and delivery assurance as TCP. FTP, being a protocol for file transfer, is not typically a focus for load balancers, which generally operate at the network or transport layer rather than the application layer where FTP resides.