Lan switch and POE adaptors

[angarato_surion]

hi can i make a question is it possible some to install lan hub after  the PoE adaptor or not  if he want to connect many Pc's in the same room but does nto have many sockets in the wall and he does not want wifi ? ( My sister and my mother they are like  wifi is not good for pregnant women etc kind of crap ..  my sister is not pregnant ..)

[KuJoe]

The PoE adapter (injector?) is used to provide power to devices through the ethernet cable so if your hub (switch?) required PoE then you'll need it. If you have another device on your network that needs it you'll need to plug the copper cable from the PoE adapter into that device directly.

[brwainer]

I think you might be talking about Powerline, which is ethernet over the power wires - PoE is the opposite, it's using ethernet wires to carry power. You can connect a switch to any powerline adaptor and it will work properly. 

[Trikein]

Are you trying to use powerline to connect PC's to the internet, or just together? PC > Powerline 1 > Powerline 2 > Switch > Multiple PC? Or Router > Powerline 1 > Powerline 2 > Switch > Multiple PC? If the former, that won't work unless you configure the PC's in a specail way. Powerline works as a bridge, so it would be like connecting a PC to a PC with a ethernet. Possible, but you need to set IP settings for a Ad-hoc network and worry about things like cross over vs patch cables. If the latter, it should work. 

[brwainer]

1 hour ago, Trikein said:

Are you trying to use powerline to connect PC's to the internet, or just together? PC > Powerline 1 > Powerline 2 > Switch > Multiple PC? Or Router > Powerline 1 > Powerline 2 > Switch > Multiple PC? If the former, that won't work unless you configure the PC's in a specail way. Powerline works as a bridge, so it would be like connecting a PC to a PC with a ethernet. Possible, but you need to set IP settings for a Ad-hoc network and worry about things like cross over vs patch cables. If the latter, it should work. 

All modern computers and almost all modern switches (invluding those built into consumer routers) have Auto-MDIX ports. (Modern meaning the last decade or so) That means they swap their TX and RX as needed for connectivity, this is set up and detected during the link up process when the devices also negotiate what speed and duplex settings can be used. Therefore crossover cables aren't a concern anymore unless connecting older hardware. And even without this - there is no reason why PC-Powerline-Powerline-switch-multiple other PCs wouldn't work - you can either leave all of them to get an autoconfiguration IP (169.254.x.x) or set up static IPs. They computers will be able to talk.

[skywake]

10 hours ago, angarato_surion said:

My sister and my mother they are like  wifi is not good for pregnant women etc kind of crap

Just on this point, the power limit for WiFi is ~4W or so. For perspective here is a map of the amount of power that you absorb when you go out in the sun:

 

That bottom line is the number of kWh/day/m^2. So lets say you went outside on an average day for a full 24 hours in somewhere that's yellow on that map. Assuming you show about 1m^2 to the sun you'll absorb ~4000Wh of power. Some of it TIR (heat), some of it visible (light) some of it UV (sunburn/skin cancer). Something which shouldn't be surprising given that you can power a house off this stuff with panels that are <40% efficient. Hell, you can power a planet of this stuff! Where do you think plants get their energy from?

 

By comparison if you hugged a router for a full day? You'd absorb ~96Wh, 1/40th of what you'd get from simply going outside. Which if anything is seriously overestimating your exposure to WiFi given the inverse square law. If you absorb 4W with your face 1cm away from a router you'll only get 0.000016W 5m away. In other words ~10,000x less than what you'd get from simply going outside. Tiny numbers, not scary even if it was as dangerous as UV which it isn't.

 

But of course nobody is scared of the sun. The thing that we all know will literally burn your skin and give you cancer. This WiFi and mobile thing is the scary thing because it's all so new. That fusion reactor in the sky is harmless... right?

[angarato_surion]

No the one side of the powerline (sorry i confused them i was meaning the powerline ) will be conneted to the vdsl router nad the other to the hub/switch