opcua

Create OPC UA client object

Syntax

uaClient = opcua(serverInfoObj)

uaClient = opcua(serverUrl)

uaClient = opcua(hostname,portnum)

Description

uaClient = opcua(serverInfoObj) creates an OPC UA client associated with the server specified by serverInfoObj. You can create server objects with the opcuaserverinfo function.

uaClient = opcua(serverUrl) creates a client associated with the server referenced by the URL specified in serverUrl.

uaClient = opcua(hostname,portnum) creates an OPC UA client object associated with the server at port portnum on the host identified by hostname.

By default, the client attempts to retrieve available connection configurations (called Endpoints) from the server and chooses the most secure possible security settings from those configurations. If the attempt to retrieve endpoints fails, an error is generated. You can override the default settings by using setSecurityModel to change the MessageSecurityMode or ChannelSecurityPolicy settings.

Note

Security Considerations: To enable a secure communication with an OPC UA server, use a strong channel security policy and message security mode.

You can expose your system to security risks when you set the MessageSecurityMode and ChannelSecurityPolicy to "None" using the setSecurityModel function. Use this setting only in a trusted environment.

If you need to connect to an OPC UA server that does not support a security policy, request the server administrator to enable a strong channel security policy and message security mode for the server. These settings enable encryption and authentication and safeguard your data and operations.

Examples

Create OPC UA Clients

Create a client for the first server found on the local host.

s = opcuaserverinfo("localhost");
uaClient = opcua(s(1));

Create a client for the server at port 53530 on the local host.

uaClient = opcua("localhost",53530)

uaClient = 

OPC UA Client:

   Server Information:
                     Name: 'SimulationServer@localhost'
                 Hostname: 'localhost'
                     Port: 53530
              EndpointUrl: 'opc.tcp://localhost:53530/OPCUA/SimulationServer'

   Connection Information:
                  Timeout: 10
                   Status: 'Disconnected'
              ServerState: '<Not connected>'

   Security Information:
      MessageSecurityMode: SignAndEncrypt
    ChannelSecurityPolicy: Aes256_Sha256_RsaPss
                Endpoints: [1×11 opc.ua.EndpointDescription]

Create a client using the Discovery URL of the server.

uaClient = opcua("opc.tcp://localhost:53530/OPCUA/SimulationServer");

Input Arguments

serverInfoObj — OPC UA server information object

opc.ua.ServerInfo object

OPC UA server information object, specified as an opc.ua.ServerInfo object.

Data Types: object

serverUrl — OPC UA server URL

char | string

OPC UA server URL, specified as a character vector or string. The server URL must use the opc.tcp protocol; Industrial Communication Toolbox™ does not support http or https connections to an OPC UA server.

Data Types: char | string

hostname — Server hostname or IP address

char | string

Server hostname or IP address, specified as a character vector or string. A hostname can be short or a fully qualified domain name.

Example: 'localhost'

Data Types: char | string

portnum — Server host port number

numeric

Server host port number, specified as a numeric value.

Example: 5000

Data Types: single | double | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64

Output Arguments

uaClient — OPC UA client

opc.ua.Client object

OPC UA client, returned as an opc.ua.Client object, with these properties.

Property	Description
Server Information
Name	Server name.
Hostname	Server hostname or IP address.
Port	Port number used for TCP/IP connections to the server.
EndpointUrl	URL to use for connection to the server.
Connection Information
Timeout	Time to wait for all operations on the server to complete.
Status	Status of the client: 'Connected' or 'Disconnected'.
ServerState	State of the server: 'Running', 'Failed', 'No Configuration','Suspended', 'Shutdown', 'Test', 'Comms Fault', 'Unknown'.
Security Information
MessageSecurityMode	Message security mode specified for connection.
ChannelSecurityPolicy	Channel security policy specified for connection.
Endpoints	Available endpoints for server.
Server Limits (These properties are available only after you connect the client to the server)
MinSampleRate	Minimum sample rate in seconds that the server can generally support.
MaxReadNodes	Maximum number of nodes supported per read operation.
MaxWriteNodes	Maximum number of nodes supported per write operation.
MaxHistoryReadNodes	Maximum number of nodes supported by historical read operations.
MaxHistoryValuesPerNode	Maximum history values returned per node in historical read operations.

Version History

Introduced in R2015b