Running Ethernet over existing coaxial cable
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Running Ethernet over existing coaxial cable
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Re: Running Ethernet over existing coaxial cable
#2AIUI the minimum latency on these is always measured in milliseconds, with 6-7ms apparently commonplace, which you're going to immediately feel using e.g. a block or network storage protocol. No references, but did look at moca for exactly the same reason a few months back. The physical size of the models I looked at also suggested you'd want to check power consumption before stuffing a home full of them - custom devices in a small market segment often drink electric.
I'd much prefer a consistent <1ms latency 10 Mbit connection than 10ish ms gigabit with 100ms spikes when next door boils their kettle, etc.
Re: Running Ethernet over existing coaxial cable
#3I have these to get wired connection from my rack to my home office, to add in a WAP and wire my desk computers. They've worked solidly and I get great throughput. I'm not a gamer so I can't speak to latency but I'd imagine if the tradeoff was this or wifi, this would still be a more desirable option.
I'm self-limited to 1G because what supports 2.5G these days? Not my equipment.
Re: Running Ethernet over existing coaxial cable
#4I have tried MOCA, but it runs at higher frequencies than cheap European coaxial was designed for (lower frequencies for terrestrial television) and had stability/performance issues due to this.
There's an alternative called G.hn over Coaxial, that runs at 100-200Mhz which seems to fair much better on crappy coaxial, at the cost of max bandwidth (500Mbps-1000Mbps) and harder to get hardware.
The manufactures of G.hn2 Coaxial adapters seem to be stingy about selling them to individuals.
Re: Running Ethernet over existing coaxial cable
#5AIUI the minimum latency on these is always measured in milliseconds, with 6-7ms apparently commonplace, which you're going to immediately feel using e.g. a block or network storage protocol. No references, but did look at moca for exactly the same reason a few months back. The physical size of the models I looked at also suggested you'd want to check power consumption before stuffing a home full of them - custom dev…
If you’re not using any splitters and zero to a few couplers you can expect latency to be ~3ms with the model OP is using. You can easily achieve 1Gbps using NFS with 3-10ms of latency as long as the underlying hardware can support it. I would avoid doing block storage even over ethernet though, that should be reserved for DAC or fiber. These particular adapters are rated for 10W (5V/2A) and I doubt they use all of that. I haven’t seen any noticeable latency spikes using these either but your mileage will vary depending on your cabling and connections (especially older pre-digital cable splitters.)
Re: Running Ethernet over existing coaxial cable
#6There’s something even better than MOCA. Black electrical tape. You tape the cat5 to the end of the coax and then pull really hard and then you get great performance.
Re: Running Ethernet over existing coaxial cable
#7There’s something even better than MOCA. Black electrical tape. You tape the cat5 to the end of the coax and then pull really hard and then you get great performance.
If the cables were run in conduits AND if there aren't any sharp turns AND if you own the place or got your landlord's permission.
Re: Running Ethernet over existing coaxial cable
#8There’s something even better than MOCA. Black electrical tape. You tape the cat5 to the end of the coax and then pull really hard and then you get great performance.
If the cables were run in conduits AND if there aren't any sharp turns AND if you own the place or got your landlord's permission.
Yes. All true. I just hate the coax in my house. It pisses me off every time I see there they installed it by just drilling a hole in the facade.
Re: Running Ethernet over existing coaxial cable
#9There’s something even better than MOCA. Black electrical tape. You tape the cat5 to the end of the coax and then pull really hard and then you get great performance.
I did the same thing but actually pulled the original coax back through as well. It's just like a permanent pull cord now. The stuff is too small to be useful for anything anyways, might as well live out the rest of its life sitting in a wall cavity.
Re: Running Ethernet over existing coaxial cable
#10I have tried MOCA, but it runs at higher frequencies than cheap European coaxial was designed for (lower frequencies for terrestrial television) and had stability/performance issues due to this. There's an alternative called G.hn over Coaxial, that runs at 100-200Mhz which seems to fair much better on crappy coaxial, at the cost of max bandwidth (500Mbps-1000Mbps) and harder to get hardware. The manufactures of G.hn2…
Given that WiFi is meant to work over the air, you could probably get a set of access points, RP-SMA to type-F adapters, and a set of attenuators and connect them back to back over basically any random coax. The loss is higher in the coax than in the air but there should be a noise floor consistent with transistor noise at room temperature.
You'd want to start with as many pads as possible, so something like >80 dB of pad. Remove them one on by one until the reported signal level is in the middle of the acceptable range.
From the device perspective it won't really know the difference. You might need to disable antenna diversity as otherwise the APs might attempt to use one of the antenna ports with nothing connected to it.