How to publish or subscribe to secure OPC UA PubSub messages

Publish secure messages in UADemoPublisher

Enter the following command at the UADemoPublisher> prompt:

publish --EnabledConnection DynamicLayoutConnection --EnabledDataSetWriter SimpleWriter --SecurityMode SignAndEncrypt --SecurityKeyServiceUri opc.tcp://localhost:48010 --SecurityKeyServiceMessageSecurity SignAndEncrypt --SecurityKeyServiceUserInfo root:secret --SecurityGroupId TestGroup --SaveConfiguration

Explanation of the command line arguments and options used:

--EnabledConnection DynamicLayoutConnection

Normally, messages are published on multiple connections. For easier troubleshooting, this option selects just one of them.

--EnabledDataSetWriter SimpleWriter

Normally, multiple dataset writers contribute to a network message. For easier troubleshooting, this option selects just one of them.

--SecurityMode SignAndEncrypt

Specifies the security mode for the PubSub network messages produced.

--SecurityKeyServiceUri opc.tcp://localhost:48010

Specifies the URL of the SKS (Security Key Service) endpoint.

--SecurityKeyServiceMessageSecurity SignAndEncrypt

Specifies the security mode that will be used to connect to the SKS.

--SecurityKeyServiceUserInfo root:secret

Specifies the user name and password used for "logging in" to the SKS.

--SecurityGroupId TestGroup

Specifies the Id of the security group in the SKS that will be used (the security group in the SKS is configured to use certain security policy, and has other parameters detailing how the security keys are generated).

--SaveConfiguration

Tells the application to create a file named UADemoPublisher.uabinary with the configuration the publisher is using (influenced by all the other options provided). The configuration file also contains metadata for the published datasets, and might be used by subscribers in consuming the published messages.

Subscribe to secure messages in OpcCmd utility

Enter the following command at the OpcCmd> prompt:

uaSubscriber subscribeDataSet opc.udp://239.0.0.1:4840 --SecurityMode SecuritySignAndEncrypt --SecurityKeyServiceUri opc.tcp://localhost:48010 --SksTemplateMessageSecurity SecuritySignAndEncrypt --SksTemplateUser root:secret --SecurityGroupId TestGroup

Explanation of the command line arguments and options used:

opc.udp://239.0.0.1:4840

The URL of the UDP multicast group on which the subscriber will be listening for PubSub network messages.

--SecurityMode SecuritySignAndEncrypt

Specifies the security mode for the PubSub network messages received.

--SecurityKeyServiceUri opc.tcp://localhost:48010

Specifies the URL of the SKS (Security Key Service) endpoint.

--SksTemplateMessageSecurity SecuritySignAndEncrypt

Specifies the security mode that will be used to connect to the SKS.

--SksTemplateUser root:secret

Specifies the user name and password used for "logging in" to the SKS.

--SecurityGroupId TestGroup

Specifies the Id of the security group in the SKS that will be used (the security group in the SKS is configured to use certain security policy, and has other parameters detailing how the security keys are generated).

Enable security event tracing in command-line tools

Use the following command in the OpcCmd utility or in UADemoPublisher (at the beginning of the program session) to enable tracing of security-related events:

!diagnostics switches setValue 1 --multiple --contains Security --typeName BooleanSwitch

Use the following command to show the trace entries after a command has been run:

traceEntries?

Related reading

• Using OpcCmd Utility as OPC UA PubSub Subscriber
• UADemoPublisher Basics
• GetSecurityKeys Method