http://rcp.net/
http://www.neuber.com/taskmanager/process/rpcnet.exe.html
There is a mountain of stuff that comes up with your search, I can understand your confusion.
Anywhere from remote controlers, to malware. See if you can find it on your machine, then control click on it>get info and see if there is more to the extension, and thus be able to do a more refined search. If your Mac is blocking it it may be malware and your Mac is doing it's job.
You can try going to your user Library and check internet plug ins, as well as disabled internet plug ins, you may also check your system Library internet plug ins, and disabled internet plug ins.
If you find anything that fits the description, highlight it and COMMAND delete, check both locations, and do the same in both. (delete all files that seem to be associated with it.
Then do a secure empty trash.