Doesn't really matter though, still means (Slightly oversimplified) that a peer can connect to 10 hosts and not have to download at all from the origin server. Also this simply isn't true in a lot of European countries where upload and download speeds are equal, but that's a different thing.

The math still does not work out.

On an 1:10 asymmetric connection, users would need to remain available for seeding 10 times longer than it takes to download (and presumably watch) the film to have a net positive impact on the system.

That's not exactly realistic, considering that a lot of traffic goes to mobile devices where this would outright kill battery life.

And Smart TVs which lack the computational power/storage/memory to serve traffic.

Can you explain what you mean by that last statement? It does not sound true to me. As far as I can tell (in my country) almost all consumer offers are asymmetric: ADSL, obviously, but also fiber. Symmetric offers are very much for professional access, and typically more expensive.

In Sweden, fiber (which is quite common) is pretty much always symmetric. 100/100 is common, many people have 1000/1000 and there is residential symmetric 10 Gb/s to be had. Asymmetric ADSL and Cable is definitely not uncommon though.

If you’re downloading ten segments from ten different uploaders it can all balance out I think.

Bittorrent can be damn quick. Haven’t used it in a while but it was certainly fast on well seeded items.

Bittorrent would eat all of the available bandwidth if the content is popular enough that there are always new leachers available.

With enough bandwidth Bittorrent would be less efficient than a single stream TCP between the source and destination because of the protocol overhead.

Yeah, but my residential conncetion is 1000/100.

Maybe 10 years ago? I don't know anyone with a connection that badly asymmetrical.

My connection is 1000/50 – theoretically.

On a good day, that works out to about 100/2, thanks to my provider vastly overselling their shitty overcongested network as "fiber to the home". (It's just cable.)

So you've got a "gigabit connection" (in marketing terms), yet worst case your upload speed is like that of ADSL. That's unacceptable.

That's not the bottleneck. The bottleneck is the IP interconnect capacity between edge network and its peers. If you only have 4x100 Gbit/sec IP sink to Level3 in SEA and your other sink is 100G to NTT, no amount of traffic engineering in your edge network is going to give you more than 500 Gbit/sec of exit and that exit will only be available if NTT has entire 100Gbit/sec that is not congested and Level3 has 400Gbit/sec not congested.

In eyeball networks the bottleneck is not upload. It is traffic being brought into the edge network from upstreams (netflix/photos/etc)

This is a accurate explanation. Eyeballs are inbound heavy and have plenty of outbound capacity (it's also why they don't care about outbound ddos so much...). However it's important to remember that they can easily congest their internal network infra on the inbound.

That's the standard ratio for Spectrum consumer internet. The ratio actually gets worse as you increase the upload speed. They cap out at 35 Mbps upload even with 940 Mbps download.

My Comcast gigabit internet is capped at 35Mbit upload as well.

It's pretty common if your last mile technology is old, e.g. cable internet coax, or copper phone lines for ADSL.

Most Comcast plans in my area come with 5Mbit/s upload, even if the download speed is 15x to 25x that.

Most FTTH connections in Italy are 1000/100 or 1000/300 Mbit/s. I guess most people wouldn't even notice the difference in upload between 100 and 1000 Mbit/s.

I have the most expensive plan available in my area, and my speeds are 24mb/0.768mb

My parents connection in Australia is 100/3.

My connection in Germany is 50/5.

Is this cable ???. Mine is fiber and is 50/50.

It's ADSL. Cable is allegedly a bit faster in my area.

230 mb Down/ 5 mb up. Xfinity near Denver.

1000/35 for me. Yay DOCSIS.

why is docsis so slow/asymmetric?

DOCSIS is fine now, but being a cable network supporting legacy systems takes up most of the upload spectrum for any cable ISP.

You can configure cable to use more of its channels for upstream. They just don't because that would hurt downstream and force them to run more cables to make up the difference.

There's absolutely no reason you can't have symmetric cable if cable companies wanted to pay for the infrastructure.

It's not a matter of "running more cables", and not just a matter of cost. They have to complete their IPTV migration, which is a massive project, and has been in progress for years now. They also have to upgrade hardware at every single node, which is a multi-year project. With that also comes brand new noise mitigation problems.

Yes, you can configure it to use more channels for upstream, but only if you cut off television to all of those paying customers, likely losing a lot of subscribers, breaking carrier agreement contracts, lose the advertising dollars, and go out of business before you even get there. You also have to swap out all of their cable boxes, and leave whoever purchased their own box hanging.

As far as I know, no ISP in North America is currently using any DOCSIS 3.1 features for upload, and they're barely taking advantage of the features for download. Moving to OFDMA is the big barrier to opening upload speeds. The protocol supports it on paper, but turning paper into massive co-existing television and ISP infrastructure is not trivial.