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CDP Studio Documentation

  • Protocols - OPC UA I/O
  • OPC-UA-Client
  • 5.0.0

Protocols - OPC UA I/O OPC UA Node

OPC-UA-Client

OPC-UA-Client

The OPC-UA-Client component must be added to the CDP application in order to connect and interact with other devices in the OPC UA (Open Platform Communications Unified Architecture) network.

Note: CDP Studio has an OPC UA discovery functionality included. By using it you can easily create a preconfigured OPC-UA-Client for any running OPC UA server without configuring a client or nodes manually. See also OPC UA Server Discovery.

OPC-UA-Client has the following configuration properties:

PropertyDescription
EndpointHost<string>Hostname or IP address to connect. Defaults to 127.0.0.1 (localhost).
EndpointPort<unsigned short>TCP port to connect. Defaults to 4840.
ClientAppURI<string>Client application OPC UA URI. If left empty, component full name is used.
ClientAppName<string>Name of the client application to be advertised. If left empty, CDP component name is used.
Interface<string>Specific interface name (from Application configuration, e.g. 'ETH0') to be used for client. Defaults to ETH0.
SecurityMode<string>OPC UA message security mode to use. Choose between:
  • None - no security (default setting)
  • Sign - all messages are digitally signed but not encrypted
  • Sign&Encrypt - all messages are digitally signed and encrypted (best security)
SecurityPolicy<string>OPC UA security policy to use, when SecurityMode other than None is selected. Choose between:
  • Aes256_Sha256_RsaPss - the most secure option for modern systems requiring the highest security and performance (default setting). Policy is described in detail at http://opcfoundation.org/UA/SecurityPolicy#Aes256_Sha256_RsaPss
  • Aes128_Sha256_RsaOaep - a balanced option for modern systems requiring moderate security and performance. Policy is described in detail at http://opcfoundation.org/UA/SecurityPolicy#Aes128_Sha256_RsaOaep
  • Basic256Sha256 - suitable for systems requiring robust security, such as industrial automation or sensitive data applications. Policy is described in detail at http://opcfoundation.org/UA/SecurityPolicy#Basic256Sha256
  • Basic256 - this policy is no longer considered as secure and therefore should only be used in rare circumstances, when server does not support more secure policies. Policy is described in detail at http://opcfoundation.org/UA/SecurityPolicy#Basic256
  • Basic128Rsa15 - this policy is no longer considered as secure and therefore should only be used in rare circumstances, when server does not support more secure policies. Policy is described in detail at http://opcfoundation.org/UA/SecurityPolicy#Basic128Rsa15
AuthUserPwd<string>Login credentials in format [username]:[password]
TLSClientCertFile<string>Client TLS key certificate file name. Must be filled when SecurityMode other than None is selected. See also OPC UA TLS certificate setup.
TLSClientKeyFile<string>Client TLS key file name. Must be filled when SecurityMode other than None is selected. See also OPC UA TLS certificate setup.
TLSAllowURIMismatch<bool>Can be set to true to allow connection to servers with TLS certificates that do not match with their application URI. See also OPC UA TLS certificate setup.

An unlimited number of AllowedServer subelements can be added to OPC-UA-Client to configure server certificate verification on connection. Each AllowedServer has the following configuration properties:

PropertyDescription
Name<string>OPC UA server name
TLSServerCertFile<string>OPC UA server TLS certificate file to match on connection. If certificate does not match connection will be dropped by the client. See also OPC UA TLS certificate setup.

OPC-UA-Client state can be observed at runtime via these read-only properties:

EndpointURL<string>Connected endpoint URL
EndpointAppURI<string>Connected endpoint application namespace URI
EndpointAppName<string>Connected endpoint application description
EndpointProtocol<string>OPC UA protocol to use. Currently only opc.tcp (binary) protocol is supported.
CurrentState<string>State of the client. Can be Online or Offline. Initially and when a problem is detected at connection, the client is offline.
StatusCode<unsigned int>OPC UA status code of the latest connection (re)try
StatusString<string>OPC UA status string of the latest connection (re)try

Nodes

An unlimited number of client nodes can be added to the OPC-UA-Client to configure the information that must be located while connecting to the remote OPC UA server. Nodes can contain other nodes and therefore can form a complex node-tree.

The following nodes can be added hierarchically to OPC-UA-Client:

  • ClientObjectNode - for accessing OPC UA object nodes
  • ClientVariableNode - for accessing any OPC UA variable and exposing it as a CDP value (or set of values)
  • ClientMethodNode - for accessing and invoking OPC UA variable method nodes
  • EventsFromOPC-UA - for converting and forwarding OPC UA events (including conditon events e.g. alarms) as CDP events (including alarm events)

Protocols - OPC UA I/O OPC UA Node

The content of this document is confidential information not to be published without the consent of CDP Technologies AS.

CDP Technologies AS, www.cdpstudio.com

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