We’ve spent the last few years watching the slow death of telephone copper networks. Rural telcos all over the country are rapidly replacing their copper with fiber. AT&T has made it clear that they would like to get out of the copper business and tear down their old copper networks. Verizon has expressed the same but decided to sell a lot of their copper networks rather than be the ones to tear them down. And CenturyLink has started the long process of replacing copper with fiber and passed a million homes with fiber in urban areas in 2016.
Very oddly, the dying copper technology got a boost when the FCC decided to award money to the big rural copper owners like Frontier, CenturyLink and Windstream. These companies are now using CAF II money to try to squeeze one more generation of life out of clearly old and obsolete copper. Without that CAF II money we’d be seeing a lot more copper replacement.
I’ve been in the telco industry long enough to remember significant new telco copper construction. While a lot of the copper network is old and dates back to the 50s and 60s, there was still some new copper construction as recently as a decade ago, with major new construction before that. But nobody is building new telco copper networks these days, which is probably the best way to define that the technology is dead – although it’s going to take decades for the copper on poles to die.
This set me to thinking about the hybrid coaxial networks (HFC) operated by the cable companies. Most of these networks were built in the 60s and 70s when cable companies sprang up in urban areas across the country. There are rural HFC networks stretching back into the 50s. It struck me that nobody I know of is building new HFC networks. Sure, some cable companies are still using HFC technology to reach a new subdivision, but nobody would invest in HFC for a major new build. All of the big cable companies have quietly switched to fiber technology when they build any sizable new subdivision.
If telco copper networks started their decline when companies stopped building new copper networks, then we have probably now reached that same turning point with HFC. Nobody is building new HFC networks. What’s hanging on poles today is going to last for a while, but HFC networks will eventually take the same path into decline as copper networks.
There will be a lot of work and money poured into keeping HFC networks alive. Cable companies everywhere are looking at upgrades to DOCSIS 3.1 as a way to get more speeds out of the technology – much in the same way that DSL prolonged copper networks. The big cable companies, in particular, don’t want to spend the capital dollars needed to replace HFC with fiber – Wall Street will punish any cable company that tries to do so.
Cable networks have a few characteristics that give them a better life than telephone copper. Having the one giant wire in an HFC network is superior to having large numbers of tiny wires in a copper network which go bad one-by-one over time.
But cable networks also have one big downside compared to copper networks – they leak interference into the world and are harder to maintain. The HFC technology uses radio waves inside the coaxial cable as the method to transmit signal. Unfortunately, these radio waves can leak out into the outside world at any place where there is a break in the cable. And there are huge numbers of breaks in an HFC network – one at every place where a tap is placed to bring a drop to a customer. Each of the taps and other splices in a cable network are sources of potential frequency leakage. Cable companies spend a lot every year cleaning up the most egregious leaks – and as networks get older they leak more.
Certainly HFC networks are going to be around for a long time to come. But we will slowly start seeing them replaced with fiber. Altice is the first cable company to say they will be replacing their HFC network with fiber over the next few years. I really don’t expect the larger cable companies to follow suit and in future years we will be deriding the networks used by Comcast and Charter in the same way we do old copper networks today. But I think that somewhere in the last year or two we saw the peak of HFC, and from that point forward the technology is beginning the slow slide into obsolescence.