POE to a non-POE switch

[Gautam.Dey]

So, our dorm has a POE Access Point setup but the range on those AP aren't that good (big dorm corridor) and we lose connectivity a lot (YouTube is OK but gaming is a big no no). So what we wanted to do is add a gigabit switch near the LAN box (the LAN box has only one output and it's only for the AP) and from that switch, connect LAN to our PC and connect the AP to the non-POE switch with a POE injector or an adapter for the AP.

 

My question is that can we connect the POE supplied connection to the non-POE switch? Will the power in the POE-LAN damage the non-POE switch or it'll be fine? Or are there any other workarounds that we can do?

 

The AP we have is Cisco AIR-CAP2702I-A-K9 Aironet 2702i

 

Please can any networking GURU can guide me through this?

 

For basic explanation I've drawn a very basic diagram showing what I mean, hopefully it'll get things clear and convey what I'm trying to say.

Cisco AIR-CAP2702I-A-K9 Aironet 2702i

[Oshino Shinobu]

You can connect it fine. 

 

802.3af/at is auto-negotiating. It will only provide power to devices that request it. 

 

You can get PoE passthrough switches, which you could consider. Ones that take an 802.3af/at input for power to the switch and have a port that can pass it through to another device, so you don't need a powercable for the switch or the AP.

[Lurick]

This entirely depends on how the school has the network setup and if they'll allow multiple devices to connect to that port or if they have some form of security implemented on that port such as 802.1x to prevent people from doing pretty much what you're talking about. Additionally, you could ask the school how they have the Aux port setup and you might be able to run a cable from that to a switch and do what you want as well since the Aux port, I believe on the 2700 and 1700 series APs, should act as a passthrough port which would let you plug into that port and then connect a regular switch on the other side but again that all depends on how they've configured the port as well.

[Gautam.Dey]

3 minutes ago, Lurick said:

This entirely depends on how the school has the network setup and if they'll allow multiple devices to connect to that port or if they have some form of security implemented on that port such as 802.1x to prevent people from doing pretty much what you're talking about. Additionally, you could ask the school how they have the Aux port setup and you might be able to run a cable from that to a switch and do what you want as well since the Aux port, I believe on the 2700 and 1700 series APs, should act as a passthrough port which would let you plug into that port and then connect a regular switch on the other side but again that all depends on how they've configured the port as well.

I've tried the AUX port...it only shows 1Gbps connection but no internet. So I've decided to try this. So what I've said would probably work right?

[Gautam.Dey]

8 minutes ago, Oshino Shinobu said:

You can connect it fine. 

 

802.3af/at is auto-negotiating. It will only provide power to devices that request it. 

 

You can get PoE passthrough switches, which you could consider. Ones that take an 802.3af/at input for power to the switch and have a port that can pass it through to another device, so you don't need a powercable for the switch or the AP.

Can you link one (cheaper would be great)?

The one I've seen are very costly.

[KuJoe]

As long as it's 802.3af you should be fine, just be careful if it's an "active" POE connection though, I've lost two cable testers thanks to those.

[brwainer]

2 minutes ago, KuJoe said:

As long as it's 802.3af you should be fine, just be careful if it's an "active" POE connection though, I've lost two cable testers thanks to those.

I think you mean passive? Passive outputs power all the time, Active doesn’t output power until a suitable client is detected. 

[Gautam.Dey]

How can I find out if it's 802.3af or if it's active or passive?

[Oshino Shinobu]

 

11 minutes ago, Gautam.Dey said:

Can you link one (cheaper would be great)?

The one I've seen are very costly.

They're not really a cheap thing. You can get PoE switches relatively cheap, but the passthrough ones tend to be a bit pricey.

[Gautam.Dey]

6 minutes ago, Oshino Shinobu said:

 

They're not really a cheap thing. You can get PoE switches relatively cheap, but the passthrough ones tend to be a bit pricey.

Name a poe switch please. I just need them for 2 semester so I really don't want to invest a lot of money on it.

[Gautam.Dey]

I'll compare cost of both the solution and would go with the cheapest

[KuJoe]

2 hours ago, brwainer said:

I think you mean passive? Passive outputs power all the time, Active doesn’t output power until a suitable client is detected. 

Yeah that, I mistyped.

[Alex Atkin UK]

I'd be very wary of doing anything without discussing it with them first.  Not a good idea to mess with someone elses network.

[Gautam.Dey]

2 minutes ago, Alex Atkin UK said:

I'd be very wary of doing anything without discussing it with them first.  Not a good idea to mess with someone elses network.

About that, it's something we all discussed and no one here really cares about it, as long as we don't disrupt the functionality and the working of it we're good to go.

[Alex Atkin UK]

4 minutes ago, Gautam.Dey said:

About that, it's something we all discussed and no one here really cares about it, as long as we don't disrupt the functionality and the working of it we're good to go.

The reason I was concerned is surely if they are okay with it, they would advise you what will and will not work?  Without knowing that, there is a slight chance you could disrupt the functionality.

 

Although I agree with above, I think its most likely it will either work, or it wont due to being locked down.

[Gautam.Dey]

3 minutes ago, Alex Atkin UK said:

The reason I was concerned is surely if they are okay with it, they would advise you what will and will not work?  Without knowing that, there is a slight chance you could disrupt the functionality.

 

Although I agree with above, I think its most likely it will either work, or it wont due to being locked down.

The reason I'm asking, is because we just changed hostels and we've the same setup in all the hostels. So I was connected with AUX port of the AP and the LAN pass-through was working fine but in this hostel, it isn't working. I couldn't get hold of the network administrator or the engineer who set it all up so I'm looking for another method.