2N IP series, Automation Manual

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MulticastTrigger
The MulticastTrigger block defines the event generated by receiving of a command
sent via SendMulticastRequest. The request is a message sent by UDP to a multicast
address (235.255.255.250:4433) and can thus be received by multiple devices at the
same time. The message includes the command ID (Command parameter) and
additional optional Input parameters. The message can be password-secured
(Password parameter).
Input parameters
Command – define the command ID to distinguish the command types. The
MulticastTrigger block responds to the SendMulticastRequest action only if the
command identifier is the same. Any text containing the A-Z, a-z and 0-9
characters can be used for identification. The Upper/Lower case must be
respected in the command name.
CheckTime – enable/disable the check of the command receiving time against
the time value included in the command message to eliminate attacks caused by
repeating of an already processed message. Synchronised time (via the NTP
server) on all command sending and receiving devices is required for this
function.
Valid values:
disabled – message time is not checked
enabled – message time is checked (enhanced security).
The parameter is optional, the default value is . 0
Password – define the password to secure the command against unauthorised
access. The password must match the value defined in the
SendMulticastRequest action to which MulticastTrigger is expected to respond.
Output parameters
Event – the Event invoke connected Event or Action.
The MulticastTrigger event is generated whenever a mass command including the list
of user Input parameters (Params parameter, MulticastRequest action) is received.
Each of the Input parameters has a user-defined unique name and is available as a
Output parameter of the same name in the MulticastTrigger block.
Example: Suppose a mass command generated by the MulticastRequest action is
received, in which Params=“AAA=123” is included. The MulticastTrigger event which
processes this command will automatically include value 123 for the AAA output
parameter. This output parameter can be referred to in the interconnected blocks.