Managing Get And Set Service Access; Set - Allen-Bradley 1444-TSCX02-02RB User Manual

Managing GET and SET
Service Access
The initiating device must access data and manage module configuration to
communicate SET and GET commands to the various objects as defined in the
CIP™ Objects Library. However, while GET commands are allowed from any
device, for security reasons the module places restrictions on the use of SET
commands.

SET

SET service commands are used to change the module configuration. A change
to the configuration can pose a security risk. Therefore, the module does not
accept a SET command from any device other than the controller with which
the module has established a (CIP™ transport) class 1 connection, even if that
device is not accessible:
• When a class 1 connection is established, the module remembers the ID
of the connected controller. Class 3 connections include the ID of the
host device that is sending the command. If the IDs do not match, the
module compares the ID communicated with the Class 3 connection
request to that of its host controller, and disallows the connection.
• The module accepts a class 3 connection SET command only if it does
not hold a host ID. The module captures the host ID of a controller
when it establishes a class 1 connection. The ID is later removed only
when the host controller normally closes the connection, typically by
inhibiting the module, or when the module is reset.
• While not unique to a class 1 connection, the Network Status (NS)
Indicator shows the module connection status.
IMPORTANT If the host controller of the module fails such that the connection closes
unexpectedly, the module cannot be configured until that same controller is
restored or until the module has been power-cycled (type 0 or 1 reset).
Rockwell Automation Publication 1444-UM001D-EN-P - June 2018
Operate the Module Chapter 10
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