The problem is not just Comcast but everything of its ilk, and by that I mean Charter (Spectrum/former Time Warner Cable), RCN/Grande/Astound and similar giant size coax based DOCSIS3 operators. In Canada, Shaw and Rogers.
They are absolutely determined to squeeze every last dollar of ROI out of that existing coax cable plant by doing asymmetric RF channels for downstream/upstream. And not overbuilding themselves with GPON FTTH.
There's a limited amount of RF spectrum in a given coax segment and they bond it together in such a way that 85% of it is used for downstream, and some paltry amount for upstream. On a heavily loaded DOCSIS3 segment it can also be 12-13ms latency to the gateway which is an eternity in metro area networking fiber terms. So you end up with something like a 200 Mbps down x 15.5 Mbps up cable connection.
Obviously the abusive bait and switch customer acquisition and retention tactics are also a huge problem. Now they're doing additional bullshit like making special offers to bundle your cellphone service and cable together (Comcast is a MVNO on some nationwide cellular carriers), for a "discounted" price, so that it makes it more painful for you to switch your ISP service in the future if you're unhappy.
Eventually they will need to spend a spectacular amount of money to overbuild themselves because in some places the local phone company (centurylink, ziply, verizon, others) is building 1 strand of dark fiber to each house, running it to some neighborhood level splitter, and going 1G or 10GPON on it for service that approaches real symmetric gigabit to the customer. To individual single family houses.
Comcast is just the most obvious example of the problem in the incumbent cable operator industry.
I always thought the upstream speed was an artificial limitation so they could upsell "business internet" to people who wanted to host servers - and that they doubled down by reassigning your IP periodically if they saw a lot of incoming connections on layer 4. I did try hosting a server on my comcast cable internet for a while and the IP which I had for seven years prior did start changing every day - sometimes more frequently. Just a coincidence? Or is that really how they play things? When I set up Tor so I could reverse proxy into my server as a hidden service my IP stopped changing - though I did notice my IP got reassigned again a few days after I got a 4K tv and started streaming the UHD content.
> I always thought the upstream speed was an artificial limitation so they could upsell "business internet"...
No, really not that at all. As noted in a few comments here, they rolled out their local infrastructure in the era of "on demand TV", when it made sense for both the cable operators and their customers to prioritize download spectrum over upload. And that meant installing expensive analog filters all up and down their lines.
I bet they would love to offer symmetric service, but at the relatively low frequencies that coax cable operates compared with optical fiber, and the cost of replacing all those filters, there is only so much they can squeeze out of it.
I guess you could call this The First Mover Disadvantage.
At this point they've gotten plenty of money from those filters, and they should be replacing them instead of doing their best to pretend upload doesn't exist.
It's a disadvantage vs. somehow knowing the future, but in the absence of future-knowing I bet they still made more money by deploying earlier.
On the other hand a cable tv incumbent in a given metro area has a huge first mover advantage of having established the right-of-way in various places (aerial pole to pole, underground duct, etc). And is usually treated by the local government as a default utility service same as water and power so they can build whatever they want almost anywhere they want, anytime they want.
RF channels actually are a finite resource on a coax segment because the aggregate capacity of one port coming off the CMTS is considerably less than properly implemented singlemode fiber. Because most residential customer traffic is inbound, like people watching netflix or browsing the web, they allocate the capacity asymmetrically.
In addition to what everyone else is saying, even if you allocate the spectrum for upstream and downstream, downstream can be run with more data efficiency because the multiplexing is handled in one place, whereas upstream is multiplex among many modems and you can't get them as tightly synchronized. When I was looking at GPON, it would typically run at half the bitrate upstream vs downstream to make upstream multiplexing more doable.
I dunno about static vs dynamic ip. In ye olde days, there was a real capacity savings with dynamic, but I don't know very many people who don't have a 24/7 device leasing an IP anyway. It's certainly a way to get a little more revenue though.
I have cable "business internet" and I get more upstream bandwidth for a similar plan, compared to a regular residential subscriber (30 megabits vs 15 or something.) However, it all shares the same infrastructure. I still only have 4 upstream channels. Total DOCSIS upstream bandwidth is limited to about 100 to 120 megabits for the entire node (neighborhood.) If you have a couple of bandwidth hogs near by, business or residential, it's going to suck!
While there is plenty of things that can be blamed on cable providers, the allocation is asymmetric RF channels it's not something that they decide to do specifically to mess up with clients but actually part of DOCSIS standard that is made by CableLabs (yea.. with input from cable companies, yet...) . A lot of todays restriction are derived from dark ages when cable was tv and not internet. IIRC till DOCSIS 3.1 (or 3.0?) data downstream was actually framed inside mpeg segments (or something like this) .
They did manage to incrementally squeeze much more out of their infra (coax) compared to what is achievable with twisted pair.
Last house that I rented had 30+ years old coax drop that were handling 1000/30 just fine and at my current house i get 1200/30.
Yea, it sucks that upstream is limited but sometimes legacy tech is legacy tech and decisions must be made in order to properly serve all the clients on plant with all the gazillion of different devices that they have
I got lucky, the subdevelopment I live in has been upgraded from classic Centurylink DSL to “Spectrum” fiber (1gbps fiber line to the house for $60/month, no contract and no equipment or setup fees. Growing up a few blocks away, it was a comcast subscription or a 1mbps DSL line(~10yrs ago).
It’s awesome when a competitor can enter the market.
They are absolutely determined to squeeze every last dollar of ROI out of that existing coax cable plant by doing asymmetric RF channels for downstream/upstream. And not overbuilding themselves with GPON FTTH.
There's a limited amount of RF spectrum in a given coax segment and they bond it together in such a way that 85% of it is used for downstream, and some paltry amount for upstream. On a heavily loaded DOCSIS3 segment it can also be 12-13ms latency to the gateway which is an eternity in metro area networking fiber terms. So you end up with something like a 200 Mbps down x 15.5 Mbps up cable connection.
Obviously the abusive bait and switch customer acquisition and retention tactics are also a huge problem. Now they're doing additional bullshit like making special offers to bundle your cellphone service and cable together (Comcast is a MVNO on some nationwide cellular carriers), for a "discounted" price, so that it makes it more painful for you to switch your ISP service in the future if you're unhappy.
Eventually they will need to spend a spectacular amount of money to overbuild themselves because in some places the local phone company (centurylink, ziply, verizon, others) is building 1 strand of dark fiber to each house, running it to some neighborhood level splitter, and going 1G or 10GPON on it for service that approaches real symmetric gigabit to the customer. To individual single family houses.
Comcast is just the most obvious example of the problem in the incumbent cable operator industry.
https://www.youtube.com/watch?v=vbHqUNl8YFk