Billie Erin Walsh bilwalsh at
Thu May 21 00:28:24 UTC 2009

Eberhard Roloff wrote:
> Billie Erin Walsh wrote:
>> Eberhard Roloff wrote:
>>> Neil Winchurst wrote:
>>>> I have my desktop computer upstairs. My wife uses her laptop downstairs
>>>> via my wireless router (DSL G604T). She often complains about losing the
>>>> signal or it all being very slow.
>>>> I have seen a little about devolo and I wondered if anyone on the list
>>>> has it in use. It looks as if it could be useful. One possible problem,
>>>> our downstairs power plugs and the upstairs ones are on separate
>>>> circuits. At least, they have separate switches on the mains box. Would
>>>> that cause any difficulty?
>>>> TIA
>>>> Neil
>>> Yes, I use them all the time, mostly for customers that want to stop 
>>> wireless, either for performance or for radiation reasons. At the same 
>>> time they do not want to invest into Ethernet cabling.
>>> Works wonderfully. Separate Switches on the mains box are, normally not 
>>> a problem.
>>> Generally the mains box over here most often is what the devolos need to 
>>> have in common.
>>> Should they not be able to make the contact (I had this only once within 
>>> a large school building installation with about 70 devolos), you can 
>>> always have "phase-couplers" installed. With those, the devolos can 
>>> connect to each other, although they reside somewhere on 3 different 
>>> phases. Over here in Germany this clearly is a job for a qualified 
>>> electrician, although it is not very difficult to do.
>>> Nowadays I would solely install the 200Mbit devices. They perform 
>>> roughly like fast-Ethernet, when only two devolos are in use. Remember, 
>>> dLan, just as wireless, is a shared network where the available 
>>> bandwidth is evenly shared between all the connecting clients.
>>> Have some fun with your network. IMHO it cannot be much easier.
>>> Eberhard
>> OH YES, by all means get one [ laughing maniacally ]. Why not just 
>> string network cable all over town and hook it to your router. And you 
>> think Windows standard security is a joke. All it takes is for one geeky 
>> hacker type to figure out that these things are in use and it opens up a 
>> whole new world of possibilities.
>> Think about it this way. With this device all the wiring in your house 
>> on that side of the electrical supply is now carrying your network 
>> information. Number one, that wiring is now an antenna broadcasting that 
>> signal. Number two, everyone in town that is on that leg is also now 
>> connected to your system. Number three, all the wiring in town is now an 
>> antenna that picks up all sorts of radio signals that feed back into 
>> your system. Park a ham radio operator, or any radio broadcast type that 
>> uses relatively high power transmissions regularly, down the street and 
>> you will have all sorts of fun. Imagine what I could do to your system 
>> with a thousand watt signal from a few feet away. Might as well hook 
>> your system directly to my transmitter.
>> OH YES, _PLEASE run right out and buy one TODAY. Make your neighborhood 
>> hacker happy.
> I do not know where you get your knowledge from. Mine is from REALLY 
> using these devices and doing my homework. ;-)
> On the one hand, the
>   electrictiy meter is the natural limit of your network. So when all of 
> your town can connect to your network, then you are the one that is 
> paying for all of the towns electricity bills. ;-)) Just let me know 
> which town you are living in, I would love to move.

 From the Devolo website:

"Is the electric meter a natural boundary of the dLAN® network? Can my 
neighbour intrude on my network? Only in rare cases does the electric 
meter attenuate the signal to that extent. Therefore, for security 
reasons, we recommend that you always use the device's internal 
encryption. Enable it by entering a password other than the factory 
password or using the encryption button."

> Secondly it is dead easy (with the emphasis on dead and easy) to encrypt 
> those networks in a way that you can even not interconnect two or more 
> different networks on the same electricity meter. Devolo offers 
> applications for the device management and encryption that work on 
> Windows and, you will not believe it, on Linux. I just used my old 
> jaunty thinkpad to install a connection from a basement homeoffice to a 
> basement DSL router, anything nicely framed with thick walls, made of 
> ferroconcrete. Drilling walls and installing ethernet cabling was way to 
> expensive, wireless was a real joke (at least I tried) and devolo worked 
> within 10 minutes.

If one Devolo can encrypt it another would be able to de-encrypt it.

Again, from Devolo:

"The encrypted raw data could provide clues to the key, thus allowing 
access to the unencrypted raw data. In dLAN® technology, however, it is 
not possible to intercept the encrypted raw data from the electrical 
wiring, as the chip does not send encrypted data directly to the network 
interface. The chip not only encrypts the signal, but also modulates it 
directly, ensuring that it is only possible to intercept modulated data. 
That would be pointless, however, as an attacker would not have any way 
to demodulate the data."

Hogwash! Anyone with a decent knowledge of radio could "de-modulate" the 
signal in a matter of seconds. After that they have access to the "raw 
data" and encryption information becomes available.

> So instead of spreading FUD, you better read it up or try it out for 
> yourself.

Maybe you need to brush up on your radio theory and application.

> Again there is nothing like a network cable, indeed! It is very cheap, 
> very fast and very secure. Just when ethernet cabling is no option and 
> wireless is lousy, then these devices do a great job. In most cases, 
> they are simply WAY better than wireless.

Agreed as to cabling. However wifi connections don't need to be poor. If 
properly done, and with proper equipment, it should be very successful.

> Unfortunately they are not cheap. So they are only worthwhile when 
> otherwise you will have to pay for the cabling work.
> Kind regards
> Eberhard

Personally, if I was setting up a wireless system as the OP mentioned I 
would use a Linksys WRT router with dual antennas. Install the DD-WRT 
firmware on the router. Remove one antenna and place it in a location 
that isn't to obvious on the lower level. After that you can adjust the 
power levels on the router and set it up to transmit and receive on both 

Treat all stressful situations like a dog does.
If you can't eat it or play with it, 
just pee on it and walk away

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