Docklight Scripting – Simulating and Testing TCP/UDP Applications

Docklight Scripting IoT terminal is an extended edition of the Docklight RS232 Terminal / RS232 Monitor. It can establish TCP connections (TCP client mode), accept a TCP connection on a local port (TCP server mode), or act as a UDP peer IoT terminal.

Docklight Scripting is a reliable, effective and easy to learn tool for debugging network-enabled devices and IoT (Internet of Things) applications that use single endpoint-to-endpoint connections. You can simulate basic functions of your application layer protocol and use Docklight Scripting for:

  • Testing your server application without writing additional client software
  • Testing your client application with Docklight acting as server
  • Testing your application protocol before implementation
IoT terminal TCP/UDP debugging testing Docklight Scripting RS232 terminal

Docklight Scripting IoT terminal – Key Functions

Simulating application layer protocols
Docklight can send out user-defined sequences according to the protocol used and it can react to incoming sequences.

Developers of a server application can use Docklight Scripting as a test client.

IoT terminal TCP/UDP debugging testing Docklight Scripting RS232 terminal
IoT terminal TCP/UDP debugging testing Docklight Scripting RS232 terminal

Logging communication data
All communication data can be logged using two different file formats: use plain text format for fast logging and storing huge amounts of data. Or create a HTML file with styled text that lets you easily distinguish between incoming and outgoing data or additional information.

The screenshot on the left shows a MODBUS TCP session between Docklight and a Barionet network automation controller.

Detecting specific data sequences
In many test cases you will need to check for a specific sequence within the logged data that indicates a certain condition.

Docklight IoT terminal manages a list of such data sequences for you and is able to perform user-defined actions after detecting a sequence, e.g. inserting additional command descriptions as shown in the UDP communication example on the right.

IoT terminal TCP/UDP debugging testing Docklight Scripting RS232 terminal
IoT terminal TCP/UDP debugging testing Docklight Scripting RS232 terminal

Monitoring TCP connections
Docklight Scripting allows you to monitor and debug a TCP-based application with the same ease as when using RS232 ports and cables.

Instead of using a Docklight Monitoring Cable between the two devices being tested, you can run Docklight Scripting within the network and simply have the client connect to Docklight Scripting IoT terminal instead of the network-enabled product.

  • Device 1 - e.g. 192.0.0.3001
  • Docklight - e.g. 192.0.0.2
    Monitoring: Server 3001, 192.0.0.2
  • Device 2 - e.g. Server IP 192.0.0.1, TCP port 3001

Docklight Scripting – What it is not

Please note that Docklight Scripting is not a network protocol analyzer. It works on the application layer only, acting as a client or server within a network.

It is NOT a troubleshooting tool for network problems, like the well known Wireshark® (Ethereal®) network protocol analyzer.