Connectors

Connectors

The connectors layer handle data at low level to send it and receive it to/from the Internet.

The action of sending data to the Internet is called uplink and all connectors must be able to implement it.

Some connectors are able to receive operations from third systems (usually OpenGate) and answer with the operation response. This feature is implemented in a message received callback. Available operations are defined in operations section

OpenGate Connectors

The OpenGate connectors modules are responsible for sending the byte stream to Internet through the implemented protocol.

The following protocols are implemented in ODA:

• CoAP: Allow to send IoT data and receive operations
• HTTP: Allow to send IoT data.
• WebSocket: Allow to send IoT data and receive operations.
• MQTT: Allow to send IoT data and receive operations.

To add new protocols you have to implement the OpenGateConnector interface:

public interface OpenGateConnector {
    void uplink(byte[] payload, ContentType contentType);
    boolean isConnected();
}

The uplink method should send the byte array following the implemented protocol and add the content type if the protocol allows it.

The isConnected method is used to check if the connector is connected.

SCADA connectors

The SCADA connectors are specific connector for SCADA protocols that works at a higher level than byte array.

There are two available protocols:

• IEC 104
• DNP3

To implement a new protocol the ScadaConnector should be implemented:

public interface ScadaConnector {
    void uplink(int index, T value, S type, long timestamp);
    boolean isConnected();
}

The uplink method implement an uplink of the given type and value to the specified index and with the given timestamp.

The isConnected method is used to check if the connector is connected.