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The speed of cable networks has already begun to match the gigabit download speeds that come with fibre-based internet services, but when it comes to uploads, they have largely lagged behind.
However, the situation now looks likely to change, with new technology now offering a potential boost that could bring the theoretical download and upload speeds up to 10Gbps.
The theory behind the technology may even have already been proven, with Nokia-owned Bell Labs recently claiming that it had already achieve 10Gbps symmetrical speeds at one of its labs in what it claims is the world's first demonstration of the technology.
The technology, which is reportedly at the "proof-of-concept" stage of testing, would require fibre to be built most of the way towards homes, with the remaining stretch relying on cabling, although that is not expected to be a significant barrier as many of the country's current networks are already running on fibre optics.
In the press release, Nokia said: "By leveraging the XG-CABLE technology, operators can effectively use existing HFC [hybrid fibre-coaxial] cables over the last 200 meters to provide upstream speeds never before achievable due to the limited spectrum available."
The company added that its latest test showed that by using XG-CABLE with point-to-point cable topologies, it was possible to deliver 10Gbps symmetric data speeds over coaxial cable using 1.2Ghz of spectrum.
When applied to point-to-multipoint deployment, Nokia's results came in at nearly 8Gbps downstream and 7.5Gbps upstream.
The company stressed that its current prototype does not support full 10Gbps when fibre is 200 metres from homes, but were achieved over 100 metres of cable.
Nokia added that its XG-CABLE implementation "can easily integrate" with the full duplex work that CableLabs is doing for the DOCSIS (Data Over Cable Service Interface Specification) 3.1 specification.
The company claims that cable operators will subsequently be able to upgrade their networks without breaking services offered to existing modems, allowing customers to keep their older modems while also having the option to gain faster speeds by upgrading to new equipment.
In a recently released white paper, Nokia have outlined how it has managed to achieve the enabling of symmetrical speeds through full duplex technology, which allows the upload and downloads to use the entire spectrum available at the same time, when previously they would have been split into separate frequencies.
It said: "Using the spectral efficiency of DOCSIS 3.1 as a reference, each 100MHz of bandwidth yields approximately 800Mbps downstream and upstream, giving a total capacity of 10Gbps in each direction [when using 1.2GHz of spectrum]," Nokia said. Though the tests were in a lab, Nokia said it used "network elements and cabling comparable to a typical HFC network."
One of the main issues to have come out of the tests has been the fact that moving to full duplex can see transmissions between a cable mode and a company's facilities create an "echo" when they happen to be travelling in opposite directions, which in turn can cause a signal's strength to be weakened.
Nokia claims to have got round this problem by way of implementing a technique that is similar to that of noise-cancelling headphones, although it claims the approach will require fibre cables to be built deeper into networks, noting that "many operators are already pursuing a deep-fibre strategy."
