There are 4 sites in a distributed system, S1, S2, S3 and S4. Currently S1 possesses the idle token. The contents of the RN arrays of S1, S2, S3 and S4 are respectively as follows - RN₁ = [2 0 0 0], RN2 = [2 0 0 0], RN3 = [2 0 0 0], RN4 = [2 0 0 0]. The contents of the token array LN is LN = [2 0 0 0]. The queue Q is currently empty. Now, S3 wants to enter CS. S3 enters CS and while S3 is executing CS, S4 wants to enter CS. Apply the Suzuki-Kasami's broadcast algorithm and describe the steps using which S3 and S4 send REQUEST messages, how the contents of the RN and LN arrays as well as the queue Q are changed, the token is dispatched to the requesting sites, the requesting sites enter CS and after finishing execution exit the CS. Note that you have to write the steps of the algorithm as applicable to the given scenario and simply drawing and annotating a diagram will fetch NO MARKS.

There are 4 sites in a distributed system, S1, S2, S3 and S4. Currently S1 possesses the idle token. The contents of the RN arrays of S1, S2, S3 and S4 are respectively as follows - RN₁ = [2 0 0 0], RN2 = [2 0 0 0], RN3 = [2 0 0 0], RN4 = [2 0 0 0]. The contents of the token array LN is LN = [2 0 0 0]. The queue Q is currently empty. Now, S3 wants to enter CS. S3 enters CS and while S3 is executing CS, S4 wants to enter CS. Apply the Suzuki-Kasami's broadcast algorithm and describe the steps using which S3 and S4 send REQUEST messages, how the contents of the RN and LN arrays as well as the queue Q are changed, the token is dispatched to the requesting sites, the requesting sites enter CS and after finishing execution exit the CS. Note that you have to write the steps of the algorithm as applicable to the given scenario and simply drawing and annotating a diagram will fetch NO MARKS.

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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