A wireless LAN uses polling to provide communications between 10 stations and a central base station. The system uses a channel operating at 50Mbps. Assume that all stations are 100 meters from the base station and that all polling messages are 64 bytes long. The data frames are of constant length of 1250 bytes. Assume that stations indicate that they have no data frames to transmit with a 64- byte message. The polling messages and end messages are always received error free. When receiving a polling message, a station will transmit a data frame with probability 0.8 and no data frame with probability 0.2. Each bit of a data frame may be received in error with probability 105. A frame is discarded if received with one or more bit errors. The speed of signal is 3*108 m/sec. Determine the throughput of this system in Mbps. а. 19.73 b. 39.30 C. 15.98 d. 25.46 е. 39.96 f. 16.25

A wireless LAN uses polling to provide communications between 10 stations and a central base station. The system uses a channel operating at 50Mbps. Assume that all stations are 100 meters from the base station and that all polling messages are 64 bytes long. The data frames are of constant length of 1250 bytes. Assume that stations indicate that they have no data frames to transmit with a 64- byte message. The polling messages and end messages are always received error free. When receiving a polling message, a station will transmit a data frame with probability 0.8 and no data frame with probability 0.2. Each bit of a data frame may be received in error with probability 105. A frame is discarded if received with one or more bit errors. The speed of signal is 3*108 m/sec. Determine the throughput of this system in Mbps. а. 19.73 b. 39.30 C. 15.98 d. 25.46 е. 39.96 f. 16.25

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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