Which system does the CPU use to communicate with I/O modules on the same rack?

The CPU communicates with I/O modules on the same rack primarily through the backplane bus. This system is designed to facilitate the transmission of data, control signals, and power between various components within the rack. The backplane bus essentially acts as a central communication pathway, connecting the CPU to the I/O modules without the need for external wiring, thereby enabling efficient and direct interaction.

Using a backplane allows for standardized connections and ensures that various modules can communicate with each other seamlessly. This setup is critical in maintaining high performance and reliability in data processing. The backplane bus can support multiple drivers and receivers, accommodating a range of devices that may be plugged into the same system.

While other bus types exist, they serve different purposes. For example, a serial bus communicates data sequentially, which may not be suitable for the fast and simultaneous communication required in a rack system. A parallel bus, on the other hand, transmits multiple data bits simultaneously but typically requires more wiring and can face limitations in terms of distance and signal integrity. The term "universal bus" is more general and does not specify the architecture used for this particular communication context. Therefore, the backplane bus is the appropriate choice for facilitating communication between a CPU and I/O modules within the