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by hericium 1461 days ago
DSLs were capable of at least 8Mbit/s speeds close to 20 years ago. I worked for a small ISP and where were more than 100 meters (theoretical limit for cat5) between residential buildings, we were setting up 8 modems on a single UTP cable. With home internet speeds back then it wasn't a bottleneck.
4 comments

ADSL2+ can do 22Mbps at 1KM. It can do 10Mbps at 2.8KM. But without mass-manufacturing of the such a switch/access device, it will be expensive.
Wait, can DSL modems talk to each other instead of a DSLAM line card?
Not a traditional dsl modem, but these work well using dsl technology: https://www.amazon.com/Tupavco-Ethernet-Extender-Kit-Repeate...
According to the description this adds at least 660ms of latency, so might be useless for certain applications. Wonder how much the TFA solution adds.
That's pretty cool. The specs look like this is both faster and cheaper than the main link of this thread, unless I'm missing something?
I was about to point something like this out.
Its true that the specs are not symmetric in ADSL. The CO (Central Office) end is different from the CPE (Customer Premises Equipment) end, and two CPE devices cannot talk to each other. Among other things, the engineering work had to take into account that at the CO end a bunch of wires would come together and leak RF between each other.

G.SHDSL is more common in a 1:1 configuration (although I think the ends may still be not symmetric) because it was designed as a T1 replacement.

However some devices that could do a single line of CO were made, that can therefore talk to a CPE.

See also https://www.revk.uk/2017/12/its-official-adsl-works-over-wet...

Some can at least. I used Netopia SDSL routers without a DSLAM around twenty years ago to serve "high speed internet" in town in the US (Easton Maryland) a few years before they managed to get municipal broadband.
It used to be possible many years ago, when I had a DSL modem as PCI card. There was a windows software that would put it in "server mode", and then you could connect another DSL modem to it and "dial in". Not sure if this is possible anymore, but there are Ethernet repeaters that are based on DSL tech which should work in a similar way.
Most SHDSL and some VDSL can talk each other indeed. Used that capability a lot in 200xs.
They may be using the term "modem" loosely here, or rather, more generally than "home modems".

https://en.wikipedia.org/wiki/Modem

As long as you weren't stringing those cables off of rooftops. I heard too many stories of lightning strikes burning out a lot of expensive equipment.
DSL and 10BASE-T1L are not quote the same.

10BASE-T1L PHY fits on a single chip, without much of analog trickery, and the whole line encoding, signal processing is much simpler.

10BASE-T1L is what will go into 1 dollar devices, not a $100 modem.

> 10BASE-T1L is what will go into 1 dollar devices, not a $100 modem.

Which is why this $150 media converter product feels bit baffling tbh.

It's a low volume product. If there were a 100k produced the cost would be substantially lower. Not that many people need 1.6km 10Mbps connections, and many of those that do need a 1.6km connection will want more than 10Mbps.