We’re not talking enough about the aging coaxial copper networks that provide broadband to the majority of the broadband customers in the country. Comcast and Charter alone serve more than half of all broadband customers in the country.

These copper networks are getting old. Most coaxial networks were constructed in the 1970s and had an expected life of perhaps forty years. We seem to be quietly ignoring that these networks will soon be fifty years old.

There is an industry-wide consensus that telephone copper is past the end of its economic life, and most telephone networks that are still working are barely limping along. It was no surprise last October when AT&T announced that it would no longer connect new DSL customers – if the company had its way, it would completely walk away from all copper, other than as a convenient place to overlash fiber.

To some degree, coaxial networks are more susceptible to aging than telephone copper networks. The copper wire inside of a coax cable is much thicker than telephone copper wires, and that is what keeps the networks chugging along. However, coaxial networks are highly susceptible to outside interference. A coaxial network uses a technology that creates a captive RF radio network inside of the wires. This technology used the full range of radio spectrum between 5 MHz and 1,000 MHz inside the wires, with the signals arranged in channels, just like is done with wireless networks. A coaxial copper network is susceptible to outside interference anywhere along the wide range of frequencies being carried.

Decades of sun, cold, water, and ice accumulate to create slow deterioration of the coaxial copper and the sheathe around the wire. It’s vital for a coaxial sheathe to remain intact since it acts as the barrier to interference. As the sheath gets older, it develops breaks and cracks and is not as effective in shielding the network. The sheathing also accumulates breaks due to repairs over the decades from storms and other damage. Over forty or fifty years, the small dings and dents to the network add up. The long coaxial copper wires hanging on poles act as a giant antenna, and any break in the cable sheathing is a source for interference to enter the network.

Just like telcos never talk publicly about underperforming DSL, you never hear a cable that admits to poor performance in networks. But I’ve found that the performance of coaxial networks varies within almost every community of any size. I’m worked in several cities in recent years where we gathered speed tests by address, and there are invariably a few neighborhoods that have broadband speeds far slower than the rest of the network. The primary explanation for poorly performing neighborhoods is likely deterioration of the physical coaxial wires.

Cable companies could revitalize neighborhoods by replacing the coaxial cable – but they rarely do so. Anybody who has tried to buy house wiring knows that copper wiring has gotten extremely expensive. I haven’t done the math recently, but I wouldn’t be surprised if it costs much more to hang coaxial copper than fiber. You can see by the following chart how copper prices have peaked in recent years.

Big cable companies deliver decent bandwidth to a lot of people, but there are subsets of customers in most markets who have lousy service due to local network issues. I talk to cities all of the time who are tired of fielding complaints from the parts of town where networks underperform. City governments want to know when the cable companies will finally bite the bullet and upgrade to fiber. A lot of industry analysts seem to think the cable companies will put off upgrades for as long as possible, and that can’t be comforting to folks living in pockets of cable networks that already have degraded service. And as the networks continue to age, the problems experienced with coaxial networks will get worse every year.