INSYS EDGE 5.0 Series, Руководство пользователя

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GSM, GPRS, and EDGE General INSYS GPRS/EDGE 5.0 serial
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8.8.3 Calculation Example
We assume a GPRS rate for data with a 1kilobyte billing matrix, as offered by T-
Mobile and Vodafone as M2M rate.
Usually, GPRS network providers bill once daily, e.g. once a day the sum of all ac-
cumulated data since the last billing is rounded to the next billing unit (here: 1 ki-
lobyte).
Example T-Mobile: Contract M2M Connect (Date: September 2005)

Basic fee: 3.95 Euro / month

Data extension M2M Data 1 for 1 Mb free volume: 2.95 Euro / month

Data extension M2M Data 2 for 2 Mb free volume: 3.95 Euro / month

Data extension M2M Data 5 for 5 Mb free volume: 4.95 Euro / month

Data extension M2M Data 10 for 10 Mb free volume: 6.95 Euro / month
The following examples show merely the pure data transmission. When a TCP/IP
connection is established via the INSYS GPRS/EDGE 5.0 serial, data is also gener-
ated (128 byte). The INSYS GPRS/EDGE 5.0 serial will not terminate a once estab-
lished connection automatically, i.e. the amount of data for the connection setup
may be ignored.
However, the following may occur:

The remote terminal can no longer be reached (power failure in the control
center, system crash, new IP address for the control center, …)

The GSM/GPRS network breaks down temporarily

The GPRS modem has a power cut
In all cases, the INSYS GPRS/EDGE 5.0 serial will automatically attempt a new con-
nection setup to guarantee the availability of the application (attempts in inter-
vals of 20s, 80s, 320, 1280s, 1h, 1h, 1h, …).
For the M2M rates, for each (failed) connection setup attempt 1kilobyte amount
of data may be assumed (at a 1 kilobyte matrix); it is therefore recommended to
plan a reserve of 30 to 50 kb up to the according upper limit of the rate.