ITU Developing New G.fin Standard for Home Fibre Networks

The International Telecommunication Union (ITU) is developing a new standard called G.fin, which could essentially create a novel fibre optic network inside your home in order to improve the speeds and connectivity directly to residential broadband routers and wireless (WiFi) access points etc.

At present most Local Area Networks (LAN) in the home environment tend to use a mix of WiFi and copper or coax based Ethernet cables, which over short distances (up to 100 metres for the best performance) have no problem carrying multi-Gigabit data speeds (e.g. CAT8 Ethernet LAN cables can handle up to 40Gbps).

Admittedly if you really wanted to make your own optical fibre network at home then that’s already possible, although it tends to require additional adapters / converters because the vast majority of consumer broadband routers simply don’t provide native support for such connectivity (they still use copper LAN cables).

Suffice to say that there isn’t a particularly pressing need to suddenly adopt a pure end-to-end fibre approach through the home, but that hasn’t stopped the ITU from moving into the development phase of G.fin. The new standard covers the creation of high-speed fibre-based in-premises transceivers (system architecture, physical layer and data link layer specification).

ITU Statement

The performance of the access network can no longer be judged only by the connection to the home (residential gateway). It must be judged by the quality and capacity of the link extending all the way to the end-user device.

Industry has achieved significant gains in the performance of the access segment up to the residential gateway with technologies like fibre access over XGS-PON, cable access over DOCSIS and copper access over G.fast. But with many devices now competing for connectivity, in-home distribution often struggles to match the performance achieved by the access segment.

The ITU G.fin project aims to overcome this imbalance with the delivery of a cost-efficient fibre technology for connectivity in the home. Success for G.fin will be industry’s ability to achieve optimal performance right up to the end-user device.

The project will describe the use cases, architecture, data link layer and physical layer of the envisioned fibre network connecting the residential gateway to the wireless access points in the home. This home fibre network will support high throughput, low latency and connection stability for wireless connectivity in the home.

We don’t entirely agree with the statement that “in-home distribution often struggles to match the performance achieved by the access segment,” not least because we’re talking more about wired (NOT wireless) links here and most broadband lines in the UK remain far slower (i.e. we’ve yet to see many people complain that their wired LAN is too slow, with performance issues usually stemming from the WiFi and broadband side).

A bigger problem is arguably the fact that far too many consumer broadband routers still only ship with 1Gbps LAN ports, which is despite the fact that faster standards exist. Admittedly if you increase the link speed then you also need to put in a more powerful CPU, which raises the cost, but modern devices (computers etc.) can already move data (internally) faster than 1Gbps and multi-gigabit home FTTP broadband is just around the corner (it’s already the norm in some countries).

Nevertheless, we’d would love to see full optical connectivity making its way into consumer broadband routers and other LAN connect-able devices, which might eventually also open up the possibility of merging the Optical Network Unit (ONT) on Fibre-to-the-Premises (FTTP) broadband lines into the same device (this would probably require more work to ensure interoperability between rival ISP networks).

One other benefit might come from the fact that optical fibre tends to be a lot cheaper than copper-based LAN cables and they’re also thinner, which makes them easier to hide. In any case the ITU look set to develop the standard for all this over the next couple of years (2022) and we’ll be interested to see what the end result looks like, even if it may initially struggle to catch-on.

Separately, the ITU has also recently amended the G.hn family of standards enable “home networks” to achieve speeds up to 10Gbps over coaxial cable and 5Gbps over “phoneline” cables (we assume they mean twisted-pair copper, but it’s not clear). In order to do this G.hn needed to develop a new physical layer and support spectrum bandwidth of 1GHz+. The new system also allows for coexistence with current coax technologies, such as DOCSIS (e.g. Virgin Media’s HFC broadband), by moving the operating spectrum to higher frequencies.