Question

Consider the following statements about bus arbitration schemes :
A. Daisy chaining is simple but slow

B. Parallel priority arbitration provides faster response than serial methods

C. Distributed arbitration allows multiple masters to share bus control

D. Centralized arbitration increases fairness

Choose the correct answer from the options given below :

• A. A, C, D only
• B. A, B, C only
• C. B, C, D only
• D. A, B, D only

Hint:

Daisy Chaining = Simple/Serial/Slow. Parallel = Complex/Fast. Distributed = No Single Point of Failure.

Answer 1

The Correct Option is B

Bus arbitration is the process by which the next device to become the bus master is selected. 1. Evaluating the Statements:
• A (Daisy Chaining): True. It is easy to implement because it uses a single grant line that "daisy chains" through devices, but it is slow because the signal must propagate through every device.
• B (Parallel Priority): True. Unlike serial methods, parallel arbitration uses separate request/grant lines for each device, allowing the arbiter to decide much faster.
• C (Distributed): True. In distributed schemes, there is no central arbiter; all devices participate in the selection process to share control.
• D (Centralized): False. Centralized arbitration (especially daisy chaining) is often unfair because devices physically closer to the arbiter have higher priority and can "starve" those further away. 2. Final Selection: Statements A, B, and C are correct. Statement D is incorrect because centralization often inherently creates a priority hierarchy rather than increasing fairness.