DCT e-track, Руководство пользователя

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2.12. REMOTE HOST SOFTWARE [ADVANCED]
3. The server should not use a keep-alive mechanism. Using a
periodical report event generated by the unit is preferred.
4. The server should have an association between the unit’s ID and
the information from the last inbound UDP message received
from the unit. This information is the last incoming message’s
IP and Port origins so the server can route any user-query using
that IP and Port as destinations.
5. An UDP destination’s configuration flag can be set so the unit
waits for an UDP confirmation message from the server every
time an event report message is sent. This UDP wait-for-ack
option can be turned OFF but it is not advised as UDP will not
assure the delivery of reports by itself. If wait-for-ack option is
used, the server has to implement this acknowledging mecha-
nism. Otherwise and because it does not receives a confirmation
message, the unit will keep on sending the same reporting mes-
sage for ever. For more information continue with the next
paragraph.
UDP confirmation message
When waiting for confirmation, the unit expects its ID on an UDP
datagram coming from the remote server every time it sends a report.
The unit sends the report: Example
>
REV2300000000000000000000000000000000090;ID=AB12
<
After receiving this, the server’s software must send back just the
unit’s ID:
AB12
Otherwise the unit will keep on sending the same message waiting
for a confirmation.
The timeout-retry mechanism for UDP with confirmation when no
confirmation is received is as follows: Four retries are sent at a 10
seconds interval, then 6 retires are sent at a 1 minute rate interval.
Then no more sends for about 6 more minutes. After that the mech-
anism restarts.
2.12.3 Working with SMS
e-track
TM
’s may use Telephone Number Destinations to send its re-
port or to give TAIP console access via SMS messages. The Destina-
tion may be configured to send user-defined event messages intended
to be read by a person with a cellular phone or similar. The Phone
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