SCO HCI rfcomm http://en.wikipedia.org/wiki/Bluetooth_protocols SCO L2CAP RFCOMM http://en.wikipedia.org/wiki/Bluetooth_protocols RFCOMM API Bluetooth protocols wiki http://en.wikipedia.org file transfer protocol protocol L2CAP file transfer Bluetooth protocol RFCOMM API RFCOMM L2CAP RFCOMM rfcomm L2CAP RFCOMM RfComm RfComm rfcomm RfComm rfcomm RFCOMM SDP rfcomm RFCOMM RFCOMM API Bluetooth protocols rfcomm file transfer BNEP protocol