Technical data

94 Theoretical and general applications www.westermo.com
Communication with GPRS uses another procedure. GPRS is based on IP communica-
tion and the connected unit must provide an IP address before a connection can be
established.
This is done by:
… Connecting to the GPRS network.
… A dynamic address is assigned.
… The exchange of data can take place.
At the present moment in time not all operators can offer subscriptions with static
address allocation. With dynamic allocation, you do not know from instance to
instance which address has been assigned to the opposing equipment.
This is not a problem if the GPRS modem is connected to the master. The master
takes the initiative for the connection and the modem has its IP address assigned. This
means a connection can be established with equipment that has a fixed IP address, for
example, a computer.
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GPRS
GPRS
Internet
ISP
GPRS attached
Dynamic IP addresses alloted
Transmitted/Received data
GPRS attached
Dynamic IP addresses alloted
Transmitted/Received data
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