Reliability Of Communication - Siemens CP 243-1 Operating Instructions Manual

Application and properties
1.10 Safety
NOTICE
The user name and related password required to log in on an FTP server are not encrypted
when transmitted over the network in compliance with the specifications of the FTP
protocol.
1.10.3

Reliability of communication

The CP 243-1 is equipped with a "keepalive" mechanism. This means that the CP 243-1 can
recognize the failure of a communications partner or the relevant connection automatically
within a configurable period of time.
The keepalive time specified when the CP 243-1 is configured is the time after which this
internal mechanism is started and an attempt is made to reach the communications partner.
These mechanisms take approximately 10 seconds. If the communications partner cannot
be reached during this time, the CP 243-1 automatically terminates the connection to this
partner. If the CP 243-1 is the client, it then attempts to establish this connection again.
Failure of the communications partner is reported to the user with the mechanisms described
in chapter Diagnostics (Page 105).
You should always activate the keepalive monitoring mechanism on all systems involved in
communication if these systems have such a mechanism.
Note
The keepalive mechanism only works if the communications partner also supports this
mechanism in compliance with RFC 1122 and RFC 793.
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Operating Instructions, 03/2012, C79000-G8976-C244-02
CP 243-1