SV 258 PRO (AG) User Manual
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5
REMOTE CONTROL VIA 3G CONNECTION
The SV 258 PRO station is designed to be operated remotely via 3G modem.
Planning and deploying the remote-control system of the SV
258 PRO station doesn’t require any extensive
knowledge in the field of telecommunication. Once all steps described in Chapter
start working with the station via the remote-control system provided by SVANTEK.
The easiest way to establish remote control is to create a user account for the SvanNET Web-service.
5.1 I
NTERFACE FUNCTIONALITIES OF
3G
MODEM
The 3G modem enables the user a wide spectrum of interfacing capabilities using GSM based internet access.
Internet access, provided by GSM operators, comes with a set of parameters that define the visibility of the SIM
card address in the network. This address can be
public
or
private
(accessible from the outside or not) and can
be
static
or
dynamic
(same or different each time the card connects to the Internet). The set of parameters
define the spectrum of available functionalities of the station remotely accessed.
The functionalities that 3G modem offers are:
•
Main communication channel
•
SMS / E-mail alarms
•
SMS command exchange.
5.1.1 Main communication channel
Main communication channel is a TCP connection (a lossless data exchange protocol) that can be used to
exchange commands as specified by Appendix A to SVAN 958A User Manual. + assures this
connection and provides the most accurate and real-time method of performing data download, performance
validation and measurement start/stop.
Main communication channel of SV 258 PRO can be established by one of two available methods: TCP Client
or TCP Server.
The
TCP Client
is a mode of main communication channel in which the 3G Modem is configured to initiate
connection to a designated address (
remote host
). Each time a
reconnection period
(default value is 30
seconds) has elapsed, SV 258 PRO attempts to establish a TCP connection to a designated address on a
designated port (
Data Port
). Should the connection be established successfully, SV 258 PRO can exchange
commands as in TCP Server mode. Should the connection attempt fail or is broken by the
remote host
,
SV 258 PRO will attempt to connect again after another reconnection period has elapsed.
To prevent the connections from going
idle
(a state in which the connection seems active, but no data can be
transferred
– it may happen due to GSM operator terminating the link, but the TCP protocol not being able to
detect it), the station maintains the connection to the server by sending small packages of data at reconnection
period (which by default is one minute). If the transfer is not properly acknowledged by the other party, the
connection will be terminated.
Note: TCP Client mode is used in the SvanNET service.
SV 258 PRO uses the TCP Client mode to connect to SvanNET (this is the default setting of SVAN 958AG).
The user also connects to SvanNET via web browser or +, and the service creates a "bridge" between
the station and the user. In this case, the user does not need to buy more options for SIM card (public dynamic
or public static IP addresses are typically optionally payed and often hard to obtain). The essence of SvanNET
is to simplify the procedures and requirements necessary for the connection.
TCP Server
is a mode in which the 3G modem is configured to act as a server for incoming connections. The
