Technology tested

Free space optics (FSO) with a radio frequency (RF) backup

Partnering agency

Defense Information Systems Agency

Objectives

• Assess the viability of FSO for backup communications by Federal agencies
• Evaluate the long-term performance, specifically availability
•  Determine if the hybrid link would provide higher availability than a single FSO link

Test Method Overview

The NCS established a link between two DISA sites in Arlington, VA. Traffic was generated and sent across the link while various applications collected statistics on other metrics, such as throughput and link receive power.

Results Overview

The hybrid system provided an availability of 99.996 % during the testing period. The FSO link was primarily affected by fog, while the RF link was primarily affected by heavy rain.