Using the OPC Server Plugin

OPC United Architechture (OPC UA) protocol is widely used industrial communications protocol. The Canary OPC Server plugin instantiates an OPC UA Server within Witness Canary, allowing 3rd party OPC UA clients to connect and obtain data from the Witness system. The OPC UA Specifications come in multiple parts and can be obtained from the OPC Foundation website.

For customers and integrators intending to use OPC Server plugin, the documents assume a reasonable working knowledge of network communication. They are targeted at technical teams, typically with software development skills, who are integrating the output from Witness into external systems.

Technical Overview

When Witness processes alarms and health statuses, it passes all this information to Witness Canary. Witness Canary then converts this information into a suitable data format to send to external systems.

The data is transmitted as the events occur, leading to near-real time reporting.

OPC UA Specification:

OPC United Architecture Specifications

On this page:

The OPC Server Plugin

Witness Canary supports integration with many different types of external systems through the use of plugins. These are stand-alone software libraries which are dynamically loaded by Canary and contain code which knows how to convert the Witness data into the required format for the external system. Navtech Radar can easily develop bespoke plugins to interface with a specific type of equipment or application. The OPC Server plugin has been developed to provide integration to the common OPC UA standard used in highway systems.

The OPC Server plugin file is entitled Witness.Plugin.OpcServer.dll and must be present in the Witness Plugin folder which is inside the main application folder. The plugin depends on OPC Foundation's liberaries Opc.Ua.Core.dll and Opc.Ua.Server.dll which must be present in the same folder.

The plugin can be selected during setup and required files will automatically be installed in the correct location.

Configuring the OPC Server Plugin

When the plugin is installed and Canary starts, the plugin configuration settings are saved to the PluginConfiguration.xml file. This file is located in the Witness main application folder. To change the settings this file should be opened in a text editor, such as Notepad, however we would recommend an editor which is XML aware, such as Notepad++.

Once the file is open, locate the OpcServer section, as illustrated below:

Example of OpcServer Plugin Configuration

<?xml version="1.0" encoding="utf-8"?>
<Config>
  <Plugins>
    <OpcServer>
      <PluginConfig>
        <ApplicationName>Tungsten.IntegrationPlugins.OPCServer</ApplicationName>
        <ApplicationUri>http://navtechradar.com/OpcServerPlugin</ApplicationUri>
        <BaseUri>opc.tcp://localhost:51210/WitnessOpcServer</BaseUri>
        <Carriageways>
          <Carriageway Id="2" Name="Carriageway 1">
            <Sections>
              <Section RadarId="1" Id="28" Name="Section 11">
                <Rules>
                  <Rule Id="1" Name="Reversing Rule" />
                  <Rule Id="2" Name="Speed Rule" />
                  <Rule Id="3" Name="Person Rule" />
                  <Rule Id="4" Name="ERA Stopped Vehicle Rule" />
                </Rules>
              </Section>
              <Section RadarId="2" Id="29" Name="Section 12">
                <Rules>
                  <Rule Id="1" Name="Reversing Rule" />
                  <Rule Id="2" Name="Speed Rule" />
                  <Rule Id="3" Name="Person Rule" />
                  <Rule Id="4" Name="ERA Stopped Vehicle Rule" />
                </Rules>
              </Section>
              <Section RadarId="3" Id="30" Name="Section 13">
                <Rules>
                  <Rule Id="1" Name="Reversing Rule" />
                  <Rule Id="2" Name="Speed Rule" />
                  <Rule Id="3" Name="Person Rule" />
                  <Rule Id="4" Name="ERA Stopped Vehicle Rule" />
                </Rules>
              </Section>
            </Sections>
          </Carriageway>
        </Carriageways>
        <NodeConfiguration>
          <DescriptionNode>Description</DescriptionNode>
          <RaisedNode>Raised</RaisedNode>
          <LocationXNode>LocationX</LocationXNode>
          <LocationYNode>LocationY</LocationYNode>
          <ActiveNode>Active</ActiveNode>
          <SensorHealth>LastHealth</SensorHealth>
          <SensorHealthTime>LastTime</SensorHealthTime>
          <LaneIdNode>Lane</LaneIdNode>
          <SectionIdNode>SectionId</SectionIdNode>
          <SectionCountNode>SectionCount</SectionCountNode>
          <CarriagewayCountNode>CarriagewayCount</CarriagewayCountNode>
          <RadarCountNode>RadarCount</RadarCountNode>
          <ManagementServerHealthNode>ManagementServerHealth</ManagementServerHealthNode>
          <TrackEngineHealthNode>TrackEngineHealth</TrackEngineHealthNode>
          <DatabaseHealthNode>DatabaseHealth</DatabaseHealthNode>
          <RadarIdNode>RadarId</RadarIdNode>
          <TrafficDataNode>TrafficData</TrafficDataNode>
          <AveSpeedNode>AverageSpeed</AveSpeedNode>
          <AveCountNode>AverageCount</AveCountNode>
          <HeartbeatNode>Heartbeat</HeartbeatNode>
          <CountClassify>CountClassify</CountClassify>
        </NodeConfiguration>
        <GenerateCertificate>False</GenerateCertificate>
        <ServerCertificateType>Directory</ServerCertificateType>
        <ServerCertificatePath>C:\ProgramData\Navtech\CertificateStore</ServerCertificatePath>
        <ServerCertificateName>NoCertificate</ServerCertificateName>
        <UserName>admin</UserName>
        <Password>12345</Password>
        <HeartbeatInterval>5</HeartbeatInterval>
        <DisableTrafficData>False</DisableTrafficData>
      </PluginConfig>
    </OpcServer>
  </Plugins>
</Config>

Once you have made changes to the plugin configuration file then you must restart the Canary application / service for the new settings to be applied. No other modules need to be restarted.

The setting options are as follows:

ApplicationName

Application Name reported through the OPC protocol

ApplicationUri

Application Uri reported through the OPC protocol

BaseUri

Location where the OPC Server is hosted. This should be the actual Canary hosting machine name, localhost or the canary machine IP followed by an unused port and optionally location.

Carriageways

This section indicates the carriageways, sections and rules that we want to track in the OPC server.
When a highway alarm is received, only an alarm matching a configured Carriageway, Section and Rule will be processed.

Examples

A basic structure of the carriageways, indicating 1 carriageway with 1 section with 1 rule that we are interested in.

Carriageway setup

<Carriageways>
  <Carriageway Id="3" Name="Carriageway 1">
	<Sections>
	  <Section RadarId="1" Id="36" Name="Section 1">
		<Rules>
		  <Rule Id="1" Name="Reversing Rule" />
		</Rules>
	  </Section>
	</Sections>
  </Carriageway>
</Carriageways>

Attributes on Carriageways and Sections

When configuring a carriageway for the plugin, the Carriageway and Section Id attribute should be the "ID" number of the desired carriageway or section and NOT the "Carriageway ID" or "Section ID" number.

The name attribute will be used for the display name of the node in OPC. It is advised to use the Witness name for consistency.

Attributes on Rules

When configuring rules for the sections, the Id attribute should use the rule "ID".

NodeConfiguration

Customize the name for each node. Each string must be different from the other string. It is recommended to stay with the defaults.
To review the structure of the OPC nodes, please see the "Generating OPC Node Structure" section below.
Description: Name of the node for the alarm description
Raised: The last time the alarm was raised
LocationX: The X position of the Track causing this alarm is stored on this node if a track is available
LocationY: The Y position of the Track causing this alarm is stored on this node if a track is available
Active: Indicates if the alarm is active
SensorHealth: Last health from a radar or other sensor
SensorHealthTime: When the sensor health was last updated
SectionCount: Indicates the number of sections within a carriageway
CarriagewayCount: Number of carriageways being tracked
RadarCount: Number of radars or sensors having their healths tracked
DatabaseHealth: Last health of the database (Vault) module
RadarId: Radar Id of the radar in Radar healths or section radar
TrafficData: Indicates that traffic data is available for this section
AveSpeed: Traffic data average speed
AveCount: Traffic data tracks count
HeartBeat: This is an increasing overall health indicator. This indicator resets to 0 after 32767

GenerateCertificate

Defaults to True. This indicates that a server certificate will be generated if the specified one is not available. This is the recommended option.
If a custom pregenerated certificate is used, the OPC Server must be configured to match the certified application name and URI.

ServerCertificateType

Indicates where the server certificate is stored. Uses "Directory" by default.
Otherwise the certificate will be stored in the Windows Certificate store.

ServerCertificatePath

File location to store the server certificate

ServerCertificateName

On on the server certificate file

UserName

Username for the OPC login. The OPC UA client should be set up to always use this.

Password

Password for OPC login. The OPC UA client should be set up to always use this.

HeartbeatInterval

Interval, in seconds, at which the heartbeat counter on the OPC Server will count up while it is connected to the Witness system. This can be used to monitor the overall health of the OPC Server plugin.

DisableTrafficData

Setting this to true will cause the plugin to ignore traffic data and will only output the more accurate Count Classify date

Generating OPC Node Structure

To assist development or configuration of the OPC UA Client, the OPC node structure will be output to the local program data folder for reference each time the plugin is started.

Connecting to the OPC UA Server

The OPC UA client used to connect to the OPC server must be able to login through a Username and Password channel.