- Suppose that we attempt to run the sliding window algorithm with SWS = RWS = 3 and with MaxSeqNum = 5. The Nth packet DATA[N] thus actually contains N mod 5 in its sequence number field. Give an example in which the algorithm becomes confused; that is, a scenario in which the receiver expects DATA[5] and accepts DATA[0] which has the same transmitted sequence number in its stead. No packets may arrive out of order. Note that this implies MaxSeqNum > 6 is necessary as well as sufficient.

- Suppose that we attempt to run the sliding window algorithm with SWS = RWS = 3 and with MaxSeqNum = 5. The Nth packet DATA[N] thus actually contains N mod 5 in its sequence number field. Give an example in which the algorithm becomes confused; that is, a scenario in which the receiver expects DATA[5] and accepts DATA[0] which has the same transmitted sequence number in its stead. No packets may arrive out of order. Note that this implies MaxSeqNum > 6 is necessary as well as sufficient.

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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