[Wylug-discuss] Technical enlightenment request

[Graham Whaley]

Ah, I think I see the confusion here....
 I was talking about 'power over ether' - where you send power over a
network cable.
 I think what you have is 'ether over power' - where you send ethernet
over a power cable - sort of the complete opposite :-)
 What you have are often called 'powerline adapters' I think. I have
some of those so I can run my printer up in the loft without having to
find a way to run an extra cable 3 floors.
The technology of powerline adapters seems to be ever improving. Mine
are probably 2 years old and have been rock solid on reliability, but
I never test them on their bandwidth capability.
Nicely, there are powerline adapter standards, and these days I think
most of the brands will probably work together OK. But, I would
suspect the 'network' of them will run at the speed of the slowest
one. If you are having bandwidth issues you may want to look at what
the current ones speed ratings are (normally measured in megabits/s).
Top whack used to be 150mbps, but now I see 500mbps advertised.

You could probably do a quick test of how well they are actually
working by timing a large transfer to your NAS to give you a feel for
actual speed as well?

 Graham


On 29 July 2015 at 09:18, Gary Stainburn <gary.stainburn at ringways.co.uk> wrote:
> Hi Anne,
>
> As Graham has alluded to, I think you're confusing two things here.
>
> POE is designed to drive low power (usually) network related devices.
>
> Example devices are VOIP phone sets, WIFI access points.
>
> I doubt very much that your printer, laptops, NAS device etc. are being
> powered by POE.  Do they not have their own power supplies?
>
> (Usually) POE enabled switches are pretty powerful, so I would not imagine
> that your network of ~ 5 devices will overload it.  It does of course depend
> on the type of work that you do.  If you're in to moving large image or musc
> files to / from your NAS constantly then that may bog it down a bit but
> otherwise you should be fine.
>
> If your work is heavily internet based, that would be my first thing to look
> at if you're having performance issues
>
> Gary
>
> On Tuesday 28 July 2015 23:18:50 Graham Whaley wrote:
>> I'm a little confused here - so you are running PoE to power all of
>> those devices? - you have some device (a PoE enabled network switch or
>> a PoE 'injector' somewhere in your network system) supplying the power
>> to the ethernet cables, and the devices thus do not run of normal
>> 'mains' power -yes? Either that, or you are actually asking a question
>> about mains wiring - not quite clear to me.
>> Not being a PoE expert I went and read the wikipedia article - seems
>> you can only normally upto 15-25w of power to each device, which feels
>> borderline to me for running a laptop for instance.
>>
>>  Graham
>>
>> On 28 July 2015 at 17:43, Anne Wilson <cannewilson at googlemail.com> wrote:
>> > Seeing the reference to
>> > http://www.ebuyer.com/583348-d-link-dgs-1008p-8-port-gigabit-poe-unmanage
>> >d-desktop-switch-dgs-1008p-e made me think about PoE.  Am I right in
>> > thinking that, since you feed a single line into the powerline, picking
>> > it up in various places is akin to picking it up from a switch box?
>> >
>> > In my office here (a stone building in the garden) I'm using PoE.  There
>> > is this laptop, doing most of the work, a small gizmo that feeds into
>> > the TP-Link AP, an ethernet connection to my OfficeJet mfp, and the
>> > occasional attachment of a further laptop.  Anything of importance is
>> > saved to my NAS in the house and regular backups feed to the NAS.  At
>> > times I think I'm overloading the system, as things start to slow down.
>> >  Coincidence, or real problem?  If I've understood the PoE bit
>> > correctly, then putting another switch box would only compound the
>> > problem, wouldn't it?
>> >
>> > Or do I have it completely wrong?
>> >
>> > Anne
>> >
>> > _______________________________________________
>> > Wylug-discuss mailing list
>> > Wylug-discuss at wylug.org.uk
>> > https://mailman.lug.org.uk/mailman/listinfo/wylug-discuss
>>
>> _______________________________________________
>> Wylug-discuss mailing list
>> Wylug-discuss at wylug.org.uk
>> https://mailman.lug.org.uk/mailman/listinfo/wylug-discuss
>
> _______________________________________________
> Wylug-discuss mailing list
> Wylug-discuss at wylug.org.uk
> https://mailman.lug.org.uk/mailman/listinfo/wylug-discuss