At 100 Gbps, a bit takes 10-¹1 sec to be transmitted. With the speed of light being 2 x 108 meters/sec, in 1 bit time, the light pulse achieves a length of 2 mm or 2000 microns. Since a photon is about 1 micron in length, the pulse is 2000 photons long. Thus, we are nowhere near one photon per bit even at 100 Gbps. Only at 200 Tbps do we achieve 1 bit per photon.

At 100 Gbps, a bit takes 10-¹1 sec to be transmitted. With the speed of light being 2 x 108 meters/sec, in 1 bit time, the light pulse achieves a length of 2 mm or 2000 microns. Since a photon is about 1 micron in length, the pulse is 2000 photons long. Thus, we are nowhere near one photon per bit even at 100 Gbps. Only at 200 Tbps do we achieve 1 bit per photon.

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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