20092ee132B_1_Hw5_Sol

20092ee132B_1_Hw5_Sol - U CLA Electrical Engineering...

This preview shows pages 1–3. Sign up to view the full content.

UCLA Electrical Engineering Department EE132B HW Set Solution #5 Professor Izhak Rubin Solution to Problem 1 In general, an arbitrary window size can be employed in a selective repeat ARQ. In this problem, the windows size is set to 4. The following is a possible sequence of frame transmissions. ACK D1 D5 D3 D4 D6 D7 D9 D2 D8 D10 Sender Receive Frame D1 D2 D3 D4 D5 D2 D3 D4 D6 D2 D7 D8 D9 D2 D10 D8 D10 Figure P1 T o

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Solution to Problem 2 (a) A go-back-N protocol would transmit D2, D3, and D4, and then proceed to transmit subsequent frames, e.g., D5, if any are ready. (b) A selective-repeat protocol would retransmit only frame D2, and then proceed to transmit subsequent frames. Solution to Problem 3 Under the conditions given, R = 64000 bps, K = (200+6)*8=1648 bits, n a =n h = 6*8 = 48 bits, t p = 0.010 sec, t ta = 0.020 sec, P E = 1-(1-10 -4 ) 1648 = 0.15194, so that throughput rate is equal to: ( 29 ( 29 ( 29 1 15686 bps 2 E h a p ta P K n R TH K n t t R - - = = + + + . Thus effective date is slightly over 25% of the line rate of 64 kbps. The major factors causing the low
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/12/2010 for the course EE 132B taught by Professor Izhakrubin during the Spring '09 term at UCLA.

Page1 / 4

20092ee132B_1_Hw5_Sol - U CLA Electrical Engineering...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online