User`s manual

OnCell G3111/G3151/G3211/G3251 Series User’s Manual Serial Port Operation Modes
8-10
Socket Applications
TCP Server Mode
TCP alive check time (default=7 min): This field specifies how long the OnCell
G3111/G3151/G3211/G3251 will wait for a response to “keep alive” packets before closing the TCP
connection. The OnCell G3111/G3151/G3211/G3251 checks connection status by sending periodic
“keep alive” packets. If the remote host does not respond to the packet within the time specified in
this field, the OnCell G3111/G3151/G3211/G3251 will force the existing TCP connection to close.
For socket and device control modes, the OnCell G3111/G3151/G3211/G3251 will listen for
another TCP connection from another host after closing the connection. If TCP alive check time is
set to 0, the TCP connection will remain open even if there is no response to the “keep alive”
packets.
ATTENTION
You should make sure the inactivity time value used here is less than the inactivity time value on
the GSM/GPRS configuration page. The GSM/GPRS connection must be maintained in order to
achieve the inactivity time behavior of the TCP connection.
Inactivity time (default=0 ms): This field specifies how long the OnCell
G3111/G3151/G3211/G3251 will wait for incoming and outgoing data through the serial port before
closing the TCP connection. The TCP connection is closed if there is no incoming or outgoing data
through the serial port for the specified Inactivity time. If this field is set to 0, the TCP connection is
kept active until a connection close request is received.