Re: Sigh. Another powerline adapter fail

Indeed. When I moved I was all set to hard wire the network, as per my previous home. I bought a couple of Tenda mesh units as a stop-gap and haven't looked back.

Admittedly, I only get about a third of the gigabit speeds I had with ethernet. But it's fine, and rock solid over the past 2 years.

I originally installed a video camera in my garage, linked by WiFi, but it was always flaky, often losing connection in bad weather. I tried powerline, but it couldn't work through the mix of CUs between the garage and the router. Eventually, I installed an underground cable, and it is now as steady as a rock.

That is the case. Remote access via powerline or wifi is sketchy at best,. Its fine up close.

I am running CAT 5 at a rock solid speed way further than any wifi extends.

Horses for courses. Joe Numpty likes wifi bluetooth and powerline because he is too lazy to do the job properly and doesn't mind next door hacking his devices

That is not wifi. That is tight band microwave.,

You *can* push copper to similar speeds over that distance, but realistically you would use fibre.,

Sure you can punch a 35Ghz tight beam 50 miles, and we do, but ultimately optical fibre beats it hands down on bandwith,

Radio is limited by the spectrum width and the impossibility of containing it outside of coax or waveguide: Ultimately fibre is simply cheaper.

That males it suitable for a lot of low power local cells - like wifi or blue tooth - connected by *something else*.

I've found the killer app for wired ethernet is not data, but power. Rather than running mains plus an awkward wallwart to a location to place a widget, I can instead run ethernet cable. That gets fed with both power and data from the PoE switch. Any time I need to locate a new widget I run some new ethernet, which means the wired network is gradually growing as needed, rather than putting it in in advance. If the device doesn't support PoE natively there are some cheap splitters for about $4 on Aliexpress.

Another nice benefit of PoE is you get power measurement for free and can remotely power cycle from the switch, which is handy when a widget needs to be rebooted.

Theo

It works as wifi.

In my last role I sometimes left the company wifi to use my mobile hotspot to test connectivity.

I was amused/imoressed that my laptop remained connected over 50m when I wondered round the office - with some hollow walls in the way to boot.

Back in the early 2000s the 'Pringles cantenna' was a way to DIY point to point links using the packaging of the potato snack and a couple of PCI wifi cards (802.11b 11Mbps). I recall people getting a few miles across town out of it.

However nowadays every dog has wifi so the 2.4GHz band is rammed full of interference in urban areas. I doubt you'd get anywhere near that range nowadays.

That's why the point to point stuff tends to use other bands which aren't used by wifi devices.

At a certain distance the curvature of the earth gets in the way and you need an ever taller mast to overcome it.

Indeed, fibre wins by a mile if it's feasible.

Theo

If you want the very cheapest solution for short distances, don't be afraid of mixing single-mode fibre with multimode transceivers or vice versa. The only catch is that using a single mode transceiver with multimode fibre can result in the receiver being slightly overloaded due to more of the beam being captured by the larger fibre aperture. It doesn't seem to cause a problem. Don't mix fibre types in a single run though as the losses might then be excessive.

Optical fibre can sometimes enable a route to be used that would be difficult with cat5e cable because it can be much thinner and more flexible.

John

I am looking for about 30 metres through metal mesh walls for my oil sensor. Test suggests it should just about work often enough...to be useful... But I'd rather have a POE cable, to be sure...

I had to rig a new office up for WiFi in a previous job. Could put the (Meraki) AP next to the network socket with zero worry about power (In fact you could put the AP over the hole in the wall to make it very neat).

That must be a managed switch. I have a cheap 4 port PoE dumb switch which works for me, Well worth the 20 quid it cost.

Interesting ... I am musing about providing power for an OMT via PoE - if/when I finally get FTTP, the OMT is likely to be in a spot where it is awkward to run power to.

The OpenReach OMTs are spec'd at something like 12V/2A (although I appreciate this is probably the PSU rating). Is this the sort of power I could obtain via a PoE injector/splitter? The Ethernet cable run would be a little over 5metres, I think.

Thanks, J^n

If you get a PoE+ switch or power injector and use a POE+ to 12V dc adapter this will definitely work fine. You may well be able to use PoE as the power consumption of the ONT is well under 10W. John

No, it's a Netgear 'smart' switch, which are typically desktop switches built using router-grade hardware to a low price. Bought it used on ebay, but TP-Link smart switches are usually good value:

I believe 802.3af ('PoE') is limited to 15.4W per port, while 802.3af+ ('PoE+') is 25.5W, and later standards can go higher still. In reality I suspect 15.4W is likely to be fine.

eg (not a recommendation):

Theo

Thanks for this Theo (and also John Walliker). One followup ... you mentioned/recommended here recently the RJ-45 connectors where the wire goes 'all the way through' the connector. I have a 'standard' RJ-45 crimp tool ... do those connectors need a (different) dedicated crimp tool, do you know, or will the standard one suffice?

Thanks, J^n