INSYS EDGE 5.0 Series, Manual

Page: 79 / 107

INSYS GPRS/EDGE 5.0 serial GSM, GPRS, and EDGE General
79
Note
The transmitted amounts of data consist of the sum of application
user data and the TCP packet data. The information from the TCP/IP
packets also represents a network load and will add to the total
costs.
For the entire data amount it is also important to select parameters
adjusted to the application to form TCP packets. These parameters
consist of:
The maximum set block value (default: 512 byte) (see
AT**TCPBLOCK)
The maximum waiting period (
AT**TCPAGG
).
As for GPRS, EDGE offers an always available connection for users as well; trans-
mission rates of up to 230 kbps (upload and download) are possible. Price struc-
tures, which are not time-based, make this technology suitable for regular re-
quests of plant data as well as transmission of large data amounts (e.g. video im-
ages).
8.2 Network Design
The GPRS system is intended as additional service within the scope of the GSM
system. The GPRS data exchange (GPRS = General Packet Radio Services) runs
packet-oriented, based on the Internet Protocol (IP).
The following figure shows the basic design, where the application has to provide
the TCP/IP/PPP stacks. This is required when using the standard GPRS functional-
ity of the INSYS GPRS/EDGE 5.0 serial.
Mobile application
TCP
PPP/IP
PPP/IP
GPRS carrier
IP
GPRS carrier
Router
(GGSN)
IP IP
Application server
TCP
IP
GPRS network radio components and internal GPRS network
IP
GPRS engine
Application
Remote
terminal