Optical Wireless Satellite Networks versus Optical Fiber Terrestrial Networks: The Latency Perspective

TL;DR

This paper compares optical wireless satellite networks and optical fiber terrestrial networks, demonstrating that satellite networks offer significantly lower latency for inter-continental data transmission, especially over longer distances.

Contribution

It introduces a simulation comparing satellite and fiber networks, highlighting the latency advantages of satellite networks using laser inter-satellite links.

Findings

OWSN outperforms OFTN in all tested scenarios.

Latency improvements increase with longer inter-continental distances.

Satellite networks leverage the speed of light in space for lower latency.

Abstract

Formed by using laser inter-satellite links (LISLs) among satellites in upcoming low Earth orbit and very low Earth orbit satellite constellations, optical wireless satellite networks (OWSNs), also known as free-space optical satellite networks, can provide a better alternative to existing optical fiber terrestrial networks (OFTNs) for long-distance inter-continental data communications. The LISLs operate at the speed of light in vacuum in space, which gives OWSNs a crucial advantage over OFTNs in terms of latency. In this paper, we employ the satellite constellation for Phase I of Starlink and LISLs between satellites to simulate an OWSN. Then, we compare the network latency of this OWSN and the OFTN under three different scenarios for long-distance inter-continental data communications. The results show that the OWSN performs better than the OFTN in all scenarios. It is observed that the longer the length of the inter-continental connection between the source and the destination, the better the latency improvement offered by the OWSN compared to OFTN.