Telit Wireless Solutions GE863 Manuale Utente
GE863-GPS Software User Guide
1vv0300724 Rev. 2 - 24/01/07
Due to this kind of connection, when activating the GPRS connection you must provide the network
parameters to enter through the internet point of the GPRS network ISP (Internet Service Provider)
and not the phone number to be dialed; therefore it is not possible to establish a direct point to point
GPRS connection between two modems as in CSD case, instead an internet tunneling must be done
to achieve a point to point connection between two peers.
This approach as the immediate advantage of projecting the controlling application of the GPRS
modem directly on the internet, ready to be accessed virtually from anywhere in the world at the same
cost on the GPRS; actually the billing of the GPRS connection is based on the amount of data
exchanged (number of packets transferred) independently from the time the connection is active or
where these packet must be delivered. Therefore, it is possible to leave the controlling application
always connected and ready to receive/send data on demand, while paying only for the data really
exchanged.
The drawback of the GPRS connection is that the controlling application must have its own TCP/IP
protocol stack embedded to decode the packets that arrive from GPRS and encode the ones to be
sent through the internet.
There are few considerations than must be done on the GPRS connections:
parameters to enter through the internet point of the GPRS network ISP (Internet Service Provider)
and not the phone number to be dialed; therefore it is not possible to establish a direct point to point
GPRS connection between two modems as in CSD case, instead an internet tunneling must be done
to achieve a point to point connection between two peers.
This approach as the immediate advantage of projecting the controlling application of the GPRS
modem directly on the internet, ready to be accessed virtually from anywhere in the world at the same
cost on the GPRS; actually the billing of the GPRS connection is based on the amount of data
exchanged (number of packets transferred) independently from the time the connection is active or
where these packet must be delivered. Therefore, it is possible to leave the controlling application
always connected and ready to receive/send data on demand, while paying only for the data really
exchanged.
The drawback of the GPRS connection is that the controlling application must have its own TCP/IP
protocol stack embedded to decode the packets that arrive from GPRS and encode the ones to be
sent through the internet.
There are few considerations than must be done on the GPRS connections:
• the GPRS connection speed with a GPRS class 10 multislot device is asymmetrical, 3 time
slots in reception (43200 bps max) and 2 time slot in sending (28800 bps max) or 4 time slots in
reception (57600 bps max) and 1 time slot in sending (14400 bps max).
reception (57600 bps max) and 1 time slot in sending (14400 bps max).
• The controlling application of the module must have a TCP/IP - PPP software stack to
interface with the GPRS modems.
• The controlling application must relay on some ISP that may be the Network Operator of the
SIM to gain access to the internet through the GPRS connection.
• Because of the point before, the receiving application must have internet access either.
• Since the communication is based upon TCP/IP packets, then it is possible to talk
contemporarily with more than one peer.
• When required, the data security in internet shall be guaranteed by security protocols over
the TCP/IP that must be managed by the controlling application.
NOTE: For more detailed information about GPRS connections and practical examples please refer to
the Easy GPRS User Guide
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