Which of the following is NOT a part of communications processors?

The correct choice highlights that a server manager is not typically classified as a communications processor. Communications processors are specialized devices or components in a computer system that handle communication between computers and networks. Their primary function is to facilitate the transfer of data and manage communications tasks effectively.

A multiplexer, for example, is a device that combines multiple input signals into a single output signal, effectively managing data streams. A front-end processor acts as an intermediary between a main computer and its peripherals, handling communication protocols and improving the overall efficiency of data processing. A controller is responsible for managing devices or systems to ensure proper data transmission and reception.

In contrast, a server manager primarily focuses on overseeing and coordinating server operations, such as maintaining software and hardware performance, security, and network connections. While server managers are essential in maintaining IT infrastructure, they do not directly participate in the processing or management of communications like the other components listed. This distinction firmly places server managers outside of the category of communications processors.