Spectrum Matters Even for Some Fixed Access Networks

In the coming era of gigabit Internet access, fiber to the customer might not always be the right choice. For some decades, the issue with fiber to the premises has been the business model.

And spectrum matters, even for some fixed access networks. Hybrid fiber coax, for example, essentially confines radio waves in a waveguide.

Huawei has demonstrated 25 Gbps downstream speeds on a hybrid fiber coax network running DOCSIS, the cable modem protocol. As always, if one has enough capacity, huge amounts of throughput are possible. The Huawei demonstration used 3 GHz of spectrum on the simulated cable network.

Separately, Nokia has demonstrated symmetrical 10 Gbps bandwidth on an HFC network. There are a couple of important caveats. Achieving such speeds requires fiber fairly close to the end user location (about 200 meters in the Nokia demonstration), or new methods for extending the range of frequencies that can be carried over an HFC network (Huawei dem).

DOCSIS 3.0 supports use of 1.6 Gbps downstream bandwidth.

The DOCSIS 3.1 solution, with a 1.2 GHz spectrum, used with multi-channel bonding and orthogonal frequency division multiplexing (OFDM) technologies, already can support a downstream rate of 10 Gbps.

Huawei’s demonstration extended the amount of usable coaxial cable spectrum to 3 GHz for the first time.

Huawei believes a symmetrical 25 Gbps capability can be commercialized.