7 ms·

The possibilities here with sufficiently sophisticated software and tunable hardware (deep learning of RF propagation characteristics in a building using data f

The possibilities here with sufficiently sophisticated software and tunable hardware (deep learning of RF propagation characteristics in a building using data from portable sensors) are fascinating! But honestly, MOCA already solves this problem. The MOCA 2.5 standard (https://en.wikipedia.org/wiki/Multimedia_over_Coax_Alliance#MoCA_2.5 https://en.wikipedia.org/wiki/Multimedia_over_Coax_Alliance#...) already delivers 2.5gbit total (time-multiplex) throughput which is more than enough for real-world no-compromise bidirectional gigabit ethernet on isolated runs or distributed backhaul to multiple wifi APs. I'm using this in my (115 y.o.) house now where new cable runs are impractical and the coax plant is unused.

kevin_nisbet 7y ago
I was thinking about this for a minute, I don't think this technology is valuable because MOCA already exists and can be used instead, I suspect it fits a sort of different use case. It allows antennas to be separately installed from the radios, and allowing existing coax cabling to be used for the distribution. So my read is instead of having to install power, MOCA, and various endpoints around, I can centrally install my radios/APs, and distribute the antennas if I have existing cabling, such as cabling for security cameras.
tomatocracy 7y ago
Yes - that's been my experience with MoCA too. I needed to add an AP in one room and putting a new ethernet cable would have been a huge hassle. Luckily there was an existing TV extension into the room and a pair of MoCA adaptors works perfectly over the run. It's significantly better than Powerline options. The other option to be aware of is G.hn on 2-wire telephone extension cable (that wasn't relevant in my case) - the adaptors for this seem to be more expensive and harder to find though than MoCA.
- war1025 7y ago
  What hardware are you using? I looked briefly into this since I also have coax run throughout the house unused, but it was hard for me to know what to look for.
  - variaga 7y ago
    I'm running a MoCA 1.4 network at home with a mixed set of ActionTec ECB2500C and Netgear MCA1001 Ethernet-Coax bridges. The interoperated w/ no problems. You can get newer versions that support MoCA 2.5, but I haven't tried them.
- toast0 7y ago
  > The other option to be aware of is G.hn on 2-wire telephone extension cable (that wasn't relevant in my case) - the adaptors for this seem to be more expensive and harder to find though than MoCA. If you've got (unneeded) telephone wire in your walls near where you want Ethernet, there's a good chance you have at least two pairs, which you can use for 100BaseTX, either point to point (ugh) if cable was run in bus formation as used to be common, or more usefully in more modern wiring where phone lines ran to a central location (hopefully somewhere that's appropriate to terminate ethernet near, but often at the telco DMARC on the outside of the home)
  - tomatocracy 7y ago
    Yes. You can often run Gigabit ethernet successfully over short runs of 4 pairs too, even if it's not Cat 5e.
variaga 7y ago
Happy to see MoCA get a shout- out. I spent most of 2003-2015 working on the design of MoCA chips, starting before the v1.0 spec release up through v2.5. AMA
- phonon 7y ago
  How is MoCA 2.5 different from G.hn Wave 2?
  - variaga 7y ago
    The main difference is that MoCA is designed to run over coaxial cable, and G.hn is meant for use over power lines. They have similar use cases ("route data over wires that already exist in your homes"), but different problems (MoCA: avoid interfering with your cable/satellite/cable modem feed, G.hn: deal with the absolutely abysmal signal quality on power lines, avoid accidentally broadcasting in the FM bands,...) From a modulation perspective, G.hn wave 2 and MoCA 2.0 are broadly similar. They both use OFDM as the main modulation and LDPC as the FEC. They both are scheduled networks (like 802.11, unlike wired ethernet) where a master node allocates transmission time slots to other nodes. The devil is in the details though and I'm not as familiar with the G.hn wave2 spec as MoCA, so the detail I can give you is limited.
    - vvanders 7y ago
      You alluded to it but the other difference is MoCA is shielded, EoP turns your house wires into a ton of radiating antennas across the frequency bands. I still have no idea how the FCC even approved the damn things after seeing what they do to the RF spectrum nearby.
      - variaga 7y ago
        Correct. Coax is nice and quiet in both directions. In home power wiring is basically a giant, poorly tuned antenna. I can tell you MOCA 1.0 can be made to work over powerline (at reduced bandwidth, if you rip out the RF frontend and run at baseband), and it can pass emissions, but it didn't work well enough (by % of households able to achieve >= target data rate) to be worth commercializing.
gergles 7y ago
FWIW the only commercially-available MoCA 2.5 product I've found that you can actually buy as an end user is the one at gocoax.com (not affiliated.) I've been very happy with their product.

kevin_nisbet 7y ago

I was thinking about this for a minute, I don't think this technology is valuable because MOCA already exists and can be used instead, I suspect it fits a sort of different use case. It allows antennas to be separately installed from the radios, and allowing existing coax cabling to be used for the distribution. So my read is instead of having to install power, MOCA, and various endpoints around, I can centrally install my radios/APs, and distribute the antennas if I have existing cabling, such as cabling for security cameras.

tomatocracy 7y ago

Yes - that's been my experience with MoCA too. I needed to add an AP in one room and putting a new ethernet cable would have been a huge hassle. Luckily there was an existing TV extension into the room and a pair of MoCA adaptors works perfectly over the run. It's significantly better than Powerline options. The other option to be aware of is G.hn on 2-wire telephone extension cable (that wasn't relevant in my case) - the adaptors for this seem to be more expensive and harder to find though than MoCA.

war1025 7y ago
What hardware are you using? I looked briefly into this since I also have coax run throughout the house unused, but it was hard for me to know what to look for.
- variaga 7y ago
  I'm running a MoCA 1.4 network at home with a mixed set of ActionTec ECB2500C and Netgear MCA1001 Ethernet-Coax bridges. The interoperated w/ no problems. You can get newer versions that support MoCA 2.5, but I haven't tried them.
toast0 7y ago
> The other option to be aware of is G.hn on 2-wire telephone extension cable (that wasn't relevant in my case) - the adaptors for this seem to be more expensive and harder to find though than MoCA. If you've got (unneeded) telephone wire in your walls near where you want Ethernet, there's a good chance you have at least two pairs, which you can use for 100BaseTX, either point to point (ugh) if cable was run in bus formation as used to be common, or more usefully in more modern wiring where phone lines ran to a central location (hopefully somewhere that's appropriate to terminate ethernet near, but often at the telco DMARC on the outside of the home)
- tomatocracy 7y ago
  Yes. You can often run Gigabit ethernet successfully over short runs of 4 pairs too, even if it's not Cat 5e.

variaga 7y ago

Happy to see MoCA get a shout- out. I spent most of 2003-2015 working on the design of MoCA chips, starting before the v1.0 spec release up through v2.5. AMA

phonon 7y ago
How is MoCA 2.5 different from G.hn Wave 2?
- variaga 7y ago
  The main difference is that MoCA is designed to run over coaxial cable, and G.hn is meant for use over power lines. They have similar use cases ("route data over wires that already exist in your homes"), but different problems (MoCA: avoid interfering with your cable/satellite/cable modem feed, G.hn: deal with the absolutely abysmal signal quality on power lines, avoid accidentally broadcasting in the FM bands,...) From a modulation perspective, G.hn wave 2 and MoCA 2.0 are broadly similar. They both use OFDM as the main modulation and LDPC as the FEC. They both are scheduled networks (like 802.11, unlike wired ethernet) where a master node allocates transmission time slots to other nodes. The devil is in the details though and I'm not as familiar with the G.hn wave2 spec as MoCA, so the detail I can give you is limited.
  - vvanders 7y ago
    You alluded to it but the other difference is MoCA is shielded, EoP turns your house wires into a ton of radiating antennas across the frequency bands. I still have no idea how the FCC even approved the damn things after seeing what they do to the RF spectrum nearby.
    - variaga 7y ago
      Correct. Coax is nice and quiet in both directions. In home power wiring is basically a giant, poorly tuned antenna. I can tell you MOCA 1.0 can be made to work over powerline (at reduced bandwidth, if you rip out the RF frontend and run at baseband), and it can pass emissions, but it didn't work well enough (by % of households able to achieve >= target data rate) to be worth commercializing.

gergles 7y ago

FWIW the only commercially-available MoCA 2.5 product I've found that you can actually buy as an end user is the one at gocoax.com (not affiliated.) I've been very happy with their product.