I use GPRS WRX700-R http://gsm-gate.ru/product/gprs-terminal-teleofis-wrx700-r/ and it's program (Sorry it is in Russian) You can write ip and port address to send bytes to the server. I write ftp ip and port number of my server. And it sends data. But on the server, I don't know where this bytes come. Can I write program on server that open sockets and get these bytes? If yes, how?
You can use a simple web server for example WEBrick to listen certain port. Ruby code would be(http://www.ruby-doc.org/stdlib-2.0/libdoc/webrick/rdoc/WEBrick.html):
Then you can take request and do whatever you want with the data sent: