The cable industry has largely ignored upload bandwidth in the past. DOCSIS technology that operates the cable broadband networks allows as much as one-eight of total bandwidth to be dedicated to uploading. However, many cable broadband connections are configured with something less than that, because very few homeowners, other than perhaps photographers or others professionals who routinely send big files have ever cared about upload speeds. To make matters worse, the cable industry generally has squeezed the upload data stream into the portion of a cable network spectrum that has the most noise and interference. That never mattered to most people when sending files, but it matters when trying to maintain a steady connection to a work or school WAN.
But suddenly upload speeds matter to a lot of households. Some of the current pressure on upload speeds will be mitigated as K12 students eventually return to the classroom, but there seems to be widespread consensus that we’re going to see more adults permanently working from home.
It’s going to be interesting to see how the big cable companies react to the upload crisis. I’ve not seen many of them talking about the issue publicly and I suspect they are hoping this will go away when the pandemic ends. The cable companies have to know that they will be competing against technologies that offer faster upload data speeds. AT&T built fiber in the last few years to pass over 12 million homes. Telcos like CenturyLink and Windstream are quietly building fiber in some communities. Verizon says it’s going to pass 30 million homes with its fiber-to-the-curb technology using millimeter wave spectrum. And private ISPs are edging fiber into cable markets all over the country.
The cable companies have possible solutions on the horizon. Cable Labs recently announced the release of the DOCSIS 4.0 standard that will allow cable companies to offer symmetrical bandwidth. The gear for this technology ought to hit the market starting next year, but industry tech writers who interview cable company management seem to agree that the big cable companies have no appetite for paying for a new round of upgrades.
The cable companies all upgraded to DOSCSIS 3.1 in the last few years that added the capability for a gigabit download product. The web is full of pronouncements from the CTOs of the big cable companies saying that they hope to get a decade out of this last upgrade. Are any of these companies going to be willing to make a major new investment in new technology so soon after the last upgrade? In many markets the cable companies have become de facto monopolies, and that inevitably leads to milking technology upgrades for as long as possible.
There are a few other technology upgrades on the horizon that could provide relief for upload speeds. There has been a move by several vendors to explore expanding the bandwidth used inside a coaxial cable. A coaxial cable network acts like a captive radio network that uses a big range of different frequencies. Cable systems historically used as much as 1 GHz of total spectrum. In recent years with the advent of DOCSIS 4.0 that’s been expanded to 1.2 GHz of total spectrum. The technology now exists to upgrade cable networks to 1.8 GHz. That would provide a huge additional pile of spectrum that could be dedicated to bandwidth. But such an upgrade would require changing out a lot of network components such as amplifiers, power taps, and modems. Such an upgrade might be nearly as expensive as a shift to DOCSIS 4.0.
The bottom line is that any significant changes to create more upload bandwidth inside cable networks will cost a lot of money. I bet that the big cable companies will stick with the current technology migration plan that would keep DOCSIS 3.1 for the rest of this decade. Likely the only thing that might prompt cable companies to upgrade sooner would be competitors mass deploying technologies that are marketed for having faster upload speeds. The most likely future is that the big cable companies will introduce DOCSIS 4.0 selectively in the few markets where they are feeling competitive pressure, but that most of households are not going to see the upload speeds that people now want.