You mean a Raspberry Pi?
How will get the DSLR to transmit over an IP network?
With Rasberry Pi, a lot of funcionality has already been written for you. Here is a link to something similar to what it appears you want to do. http://www.makeuseof.com/tag/how-to-capture-time-lapse-photography-with-your-raspberry-pi-and-dslr-or-usb-webcam/. It uses a gPhoto, a free app that runs on Linux to transfer files off the dslr at a fixed time lapse. John H, I imagine the link to the DSLR would be USB rather than ethernet. The FTP from the Rasberry Pi to wherever you want could be initiated from either the Pi or a remote computer.
Depending on the DSLR, Nikon I know has Wifi attachments that you can setup to send the photos to a computer.
I use this one
Apprently they get pricey now.