CSE-45593 ---------------- HW #1 ------------------ Name: ____________________

Problem 1 (25 Points)

  1. Three fundamental terms used in this course are fault, error, and, failure. In one to three sentences, clearly distinguish these terms from each other.
  2. What is the difference between a permanent fault, an intermittent fault, and a transient fault in term of fault duration?
  3. Comment on the following statement with justification. Single faults can cause multiple bit errors and multiple faults can cause single error.
  4. Comment on the following statement with justification. A fault-tolerant system necessarily has a high reliability.
  5. Define the following: reliability, availability, safety, and performability. Does a system with a high availability necessarily have a high reliability?

Problem 2 (15 Points)

Design a one bit 5MR voter.

Problem 3 (15 Points)

A certain cyclic code has the generator polynomial G(x) = x5 + x2 + 1.

  1. Generate a codeword for the input data 10101.
  2. Using logic gates, design an appropriate encoder and decoder the given cyclic code.
  3. Determine the code distance and comment on its error detection capability.

Problem 4 (20 Points)

A 2M X 16 memory system is design using 1 M X 4 chips. Assume chip failure modes are single-bit cell (50%), single-row all-0's (20%), single-column all-0's (20%), and whole-chip all-0's (10%). Also, assume 0 and 1 values are equally likely. Compare and comment on relative performance (single-error-detection coverage) and overhead of the following approaches.

  1. Bit per chip
  2. Bit per multiple chips
  3. Duplication
  4. Single precision checksum (one sum for the entire memory).

Problem 5 (15 Points)

Design the self dual of a full adder.

Due: Thursday, October 11, 2001