There are two types of protocols for STV11: SMS, another is GPRS(support TCP and UDP). The former is
suitable for personal monitoring, the latter is suitable for center monitoring.
SMS type: means the tracker would send data back via short message .
GPRS type : means the tracker would send data back via TCP/UDP. The main difference between SMS and GPRS is the GPS data sending mode is different, SMS type : GPS data would be sent to the mobile phone which defined by the user or sent to a GSM modem; GPRS TYPE : GPS data would be sent to the monitor center in hexadecimal code.