In 1991, researchers at CERN in Switzerland launched the World Wide Web (WWW). At the time, the network had a global average connection speed of just 14.4 kilobits per second (kbit/s). Modems arrived and the speed doubled in just a few years, going from 28.8 kbit/s and then to 56 kbit/s, breaking what was previously thought to be an upper limit for telephone line transmissions.
In 2005, one of the quantum leaps in information transmission took place: megabit per second (Mbit/s) was exceeded in 2005, around 20 times faster than dial-up services. This became known as broadband and paved the way for new applications such as video streaming. A decade later we have already reached 10 Mbit/s and in 2022, the global average was approximately 100 Mbit/s. But that is only the average, because more than 50 countries already offer 1 Gbit/s or more, that is, a million times faster than in 1991.
Now, a team of scientists, led by Ian Phillips of Aston University, have reacheda speed of 301 terabits per second (Tbps), equivalent to transferring 1,800 4K movies over the Internet in one second. And this using existing fiber optic cables.
Phillips' team has achieved transfer speeds of fiber optic data 1.2 million times faster than fixed broadband line average when taking advantage of a previously unstable transmission band for the first time. In comparison, the average fixed broadband speed in Spain is 238 megabits per second (Mbps).
This was possible by sending infrared light through tubular glass strands, the way fiber optic broadband generally works, but they took advantage of a spectral band that has never been used in commercial systems, called “E band”, using new custom-made devices.
The results of the test, which were carried out using the type of fiber cables already laid in the ground, were published by the Institute of Engineering and Technology (IET). Scientists built a system that made stable E-band transmission possible. They demonstrated successful and stable data transfer at high speeds using both the E-band and the adjacent S-band. All of these transmissions are carried out through the electromagnetic spectrum.
To maintain a stable connection in this region of the electromagnetic spectrum, researchers created two new devices called “optical amplifiers” and “optical gain equalizers.” The former helps amplify the signal at a distance, while the latter monitors each wavelength channel and adjusts the amplitude when necessary. They implemented them in fiber optic cables to ensure that infrared light transmitted data without the jitter and loss that typically plagues connections in these bands.
“Over the last few years, Aston University has been developing optical amplifiers that operate in the E band, which is adjacent to the C band in the electromagnetic spectrum, but is approximately three times wider – explains Ian Phillips -. “Prior to the development of our device, no one had been able to successfully emulate E-band channels in a controlled manner.”
Although 301 Tbps is extremely fast, other scientists have taken advantage of fiber optic connections to demonstrate even faster speeds in recent years. A NICT team, for example, reached the world record of 22.9 petabits per second in November 2023, 75 times faster than the speed reached by the Aston University team. But this was just a rehearsal and the connection over a distance of “barely” 13 kilometers.