Recent trials by BT using fibre optic cables have yielded record breaking results.
The company's specialists at Adastral Park in Ipswich have collaborated with Huawei on tests involving a live core network link extending more than 700km between London and Dublin.
They achieved a speed of 2Tbps, which is a brand new world record for a live network.
Researchers also managed to transmit speeds of 5.6Tbps over a single optical fibre running on its trial network between Adastral Park and the BT Tower in London.
This breaks the 3Tbps record set two years ago and is comparable to downloading nearly 200 HD quality films in a second.
Howard Watson, Chief Executive of BT Technology, Service & Operations, commented: "BT scientists built the first commercial single mode optical fibre link back in 1984 and the BT Labs remain at the forefront of photonics research more than 30 years later.
"The core network is the superhighway of the internet. It’s important that our core networks keep pace with the growth in bandwidth demands driven by take-up of high-speed fibre broadband, HD content, 4G smartphones and tablets and in the future, 5G services."
Mr Watson added that BT is investing in its core and high-speed access technology such as fibre broadband to ensure there is no capacity crunch and that broadband customers get the best possible speeds.
He described the recent tests as "landmark trials" that demonstrate BT is able to deliver the speeds needed in its core networks to stay several steps ahead of rising customer demand.