Connecting arduino on experimental setup to lab based PC

I am currently busy with a university project where i will have an experimental setup on the roof of a building at the university, and a PC in a laboratory downstairs(Cable distance approximately 15m). I am using am planning on using an arduino Leonardo and ethernet shield(only have that to my disposal), and wish to send data from the arduino to the PC, already connected to the local network via ethernet. Connecting the arduino via ethernet to the local network via the server is not an option.

What other options do i have to link the arduino and PC(sources say max US cable length is 5m??)

Can i write to an SD card on ethernet shield?

Or if i use a laptop instead, connected to internet through wifi, can i connect arduino directly to laptop via ehternet using cross over connection?

Bluetooth 4 might be satisfactory, a lot simpler, and a lot cheaper. If Arduino cannot connect to Ethernet, using an Ethernet shield doesn't sound like such a great idea but, yes, writing its SD is both possible and usual practice - to the point where it is so convenient, it is common to do it without using the Ethernet bit.

15 meter cat5 cable and serial would work just use 9600 or less send rate.

Definitely go for wireless. On the roof you're subject to lightning strikes. Even if the building's lightning protection works perfectly and your device isn't hit directly, the induced current in 15m wires can kill the PC.

There's lots of wireless solutions available for Arduinos. Start with https://www.sparkfun.com/categories/16 for some ideas.

MorganS: Definitely go for wireless. On the roof you're subject to lightning strikes. Even if the building's lightning protection works perfectly and your device isn't hit directly, the induced current in 15m wires can kill the PC.

There's lots of wireless solutions available for Arduinos. Start with https://www.sparkfun.com/categories/16 for some ideas.

Thanks for the response. Not in an area prone to any lightning strikes. Project supervisor provided me with a solution, thanks.

Hi, What was the solution? If your problem is solved, then can you please go and add the words SOLVED to the thread subject.

Thanks .. Tom... :)