UDP In

#  What is udp-in node in Node-RED?

The UDP-In node in Node-RED enables the reception of UDP messages from remote devices or services. It acts as a listener, waiting for incoming UDP packets on a specified port. This functionality is crucial for real-time applications, such as IoT data ingestion and network communication. Whether you're receiving sensor data from IoT devices or communicating with other networked systems, the UDP-In node seamlessly integrates UDP communication into your Node-RED workflows, providing a lightweight and efficient solution for data reception.

#  What is UDP?

UDP (User Datagram Protocol) is a connectionless protocol in the Internet Protocol suite. It transmits data packets, or datagrams, without establishing a connection, prioritizing speed over reliability. Commonly used for real-time applications like video streaming, online gaming, and VoIP. UDP's simplicity reduces latency but doesn't guarantee delivery of data packets. For more information refer to UDP MDN Docs.

#  Configuring UDP-In Node

The UDP-In node in Node-RED provides versatile configuration options to tailor UDP message reception according to specific requirements:

  • Listen for:

    • UDP messages: Receive standard UDP messages from remote devices or services.
    • Multicast messages: Listen for multicast messages, allowing communication with multiple recipients simultaneously.
      • Group: Specify the multicast group address.
      • Local IF: Choose the network interface to use for receiving multicast messages.

  • On port: Define the port number on which the UDP-In node will listen for incoming messages.

  • Using:

    • IPv4: Utilize IPv4 addressing for communication.
    • IPv6: Utilize IPv6 addressing for communication, supporting the latest IP version.

  • Output: Choose the format for the received data:

    • As a buffer: Receive messages as buffer objects.
    • As a string: Receive messages as strings.
    • As a base64 encoded string: Receive messages encoded in base64 format.

Note: On some systems, you may need root or administrator access to use ports below 1024 and/or broadcast, and have to ensure your firewall allows the data in.

Note: The default UDP nodes have been removed from the Node-RED palette in the FlowFuse Cloud due to limitations in routing connections to the container running Node-RED inside the FlowFuse platform

#  Usecases

  • Sensor data acquisition: Receive real-time data from IoT sensors deployed in the field, such as temperature, humidity, or motion sensor readings.
  • Device status monitoring: Monitor the operational status of IoT devices, such as connected appliances or industrial machinery, by receiving status updates over UDP.
  • Environmental monitoring: Collect environmental data from IoT devices installed in remote locations, such as air quality sensors or weather stations, for analysis and decision-making.
  • Asset tracking: Receive location data from IoT devices equipped with GPS or RFID technology to track the movement of assets, vehicles, or livestock in real-time.
  • Media stream reception: Receive media streams, such as video or audio content, for applications like CCTV surveillance, live broadcasting, or multimedia communication.

#  Example

  1. In the example below, we have a UDP-In node configured to receive data sent over localhost and port 90, using a UDP-Out node.

#  Output

  • msg.payload: Output received messages as a Buffer, string, or base64 encoded string.
  • msg.fromip: The IP address and port from which the message was received, formatted as "IP:Port".
  • msg.ip and msg.port: The IP address and port from which the message was received.

Node Documentation