For two computers to communicate end-to-end, which components are required: software, protocol, hardware interfaces, and a transmission medium?

Introduction / Context:
Reliable computer communication is a stack of interdependent pieces. Missing any one element breaks end-to-end connectivity, even if the others are present. This question checks holistic understanding of requirements beyond just cables or just software.

Given Data / Assumptions:

• Endpoints are digital computers needing interoperable components.
• Standardized rules (protocols) must be shared by both ends.
• Physical links and interface hardware are necessary to carry signals.
• Applications rely on software to implement the stack.

Concept / Approach:

Successful communication needs: (1) software (application and stack drivers), (2) protocols (rules/format like TCP/IP), (3) hardware (NICs, modems, radios), and (4) a medium (copper, fiber, radio). Deficiency in any layer prevents data exchange.

Step-by-Step Solution:

Verification / Alternative check:

A loopback test shows software/protocols working locally; unplugging the medium breaks remote communication despite software and hardware presence, demonstrating all four are needed.

Why Other Options Are Wrong:

Any single component alone cannot achieve communication; selecting only one omits indispensable layers.

Common Pitfalls:

Overlooking protocol compatibility or assuming a cable alone enables communication without drivers/software.

Final Answer:

All of the above