Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsI learned to investigate industrial protocols by asking a narrower question, building a controlled local experiment, and checking the packets—not by making the lab as elaborate as possible. For my series, that shift mattered as much as the protocols themselves: it helped me separate what I could observe from what I could reasonably infer.
Why I moved the experiments into a local lab
I began with a project called Modbus Exposure Analyzer, intended to identify exposed Modbus services and examine what they revealed. I first considered testing services I could find through Shodan. I changed course and built a local Modbus environment instead: industrial systems should not be treated as convenient targets for experimentation.
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That choice established the pattern I followed afterward: create a controlled environment, generate a specific interaction, and inspect what happened. A local lab made it possible to ask protocol questions without probing systems that did not belong to me.
When a realistic lab becomes too much lab
My early software-defined environments grew larger than the questions required. I worked with OpenPLC, FUXA, Docker, virtual machines, GNS3, and protocol implementations. Building out controllers, HMIs, engineering systems, and networks helped me understand how those pieces can fit together. But the complexity could also exceed what a particular experiment needed.
#1 Best Overall
- Double way USBCAN II Debugger with 2 Road CAN interface, PC can be connected to a standard CAN network through the USB bus, the construction of Field bus testing laboratory, industrial control, intelligent building, data processing, automotive electronic
- Double way USBCAN II debugger can be used as a standard CAN bus, CAN bus is CAN bus equipment product development, testing, a powerful tool for data analysis; at the same time, the USBCAN debugger has the characteristics of small volume, convenient insta
- Double way USBCANII The debugger can use the USBCAN tools provided by our shop, directly to the CAN bus configuration, send and receive. Users can also refer to the store to provide the DLL dynamic link library, routines to write their own applications,
- Double way USBCAN II The debugger equipment, CAN bus circuit adopts DCDC power module, industrial grade magnetic isolation chip CAN bus isolation, the interface has a strong anti-jamming capability, greatly improve the reliability of the
- Compatible universal USBCAN device
The useful lab was not necessarily the one with the most components. As I put it, “A good laboratory does not have to look impressive. It has to give you control over the experiment.” That control let me focus on a request or exchange rather than trying to reproduce an entire plant.
The workflow that made protocol questions testable
My working method became: Research question → local implementation → harness → packet capture → packet analysis → interpretation. This was my practical workflow, not a formal standard. Each stage narrowed the gap between a question and evidence.
Rank #2
- SEE BOTH SIDES AT ONCE - THIS IS A SNIFFER, NOT A USB ADAPTER: A USB-to-serial converter lets you talk to one device. diDatatracker sits passively on the line and captures BOTH directions simultaneously, merged onto one timestamped timeline. Plug in USB-C and two virtual COM ports appear, ready to capture - nothing to configure. Works with RS232, RS485 and TTL (3.3V/5V).
- 3000Vrms SIGNAL + 1500V POWER ISOLATION: A complete electrical barrier between your laptop and the bus. Blocks high-voltage spikes, ground loops and EMI on factory floors where the ground reference cannot be trusted. Competing taps at 6-11x the price do not publish an isolation rating at all.
- ALL THREE BUSES IN ONE BOX: RS232 (dual DB9 female), RS485 (dual channel terminals) and TTL at both 3.3V and 5V logic - switch between MCU bring-up and industrial PLC monitoring without level shifters or a second adapter. USB-C host connection. Windows, macOS and Linux - most systems already carry the USB serial driver it needs, and the manual shows you where to download it if yours does not.
- FREE OPEN-SOURCE SOFTWARE INCLUDED, ON GITHUB (WINDOWS): diSerial, our companion application - no licence, no subscription, no account. Both channels on one merged timeline, with recording and export. Nine interface languages. Source and download are both public under Apache-2.0, so your IT department can read every line before approving it - and it contains no network code at all. Windows 10 and 11 (x86 and ARM64); macOS in development - the hardware itself works on all three.
- About DSD TECH: Established in 2009, DSD TECH specializes in industrial connectivity solutions, delivering 80+ products (USB/RS232/UART/RS485/CAN) to 100,000+ global clients across automation and communication sectors. Every device comes with lifetime support and 1 year product replacement service.
- Write down what I want to establish. Questions might include: “How does communication start?”, “What does a legitimate exchange look like?”, “Where is trust assumed?”, or “What can an observer learn from the traffic?”
- Choose a local implementation. I treated the implementation as the experimental subject, not as a proxy for every product that supports the protocol.
- Use a small harness to generate the interaction. The harness gave me a way to produce the request or exchange relevant to the question, without building out features I did not need.
- Capture and inspect the traffic. I used Wireshark or tshark to examine the packets crossing the wire. When making a claim about on-wire behavior, the capture provided evidence to inspect rather than relying only on what an application appeared to do.
- Separate observation from interpretation. The packets can show a request, response, or changed field in a particular experiment. Any further claim—such as what that behavior implies about trust or security—needs to be identified as interpretation and kept within the experiment’s limits.
The questions that guided my work included “What does authentication actually protect?”, “What remains exposed when security mechanisms are missing?”, “What can an attacker influence?”, and “What evidence can I establish in the laboratory?” I found the last question especially useful because it forces the method to follow the claim.
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What my protocol series covered—and what it did not compare
My series covered nine protocol families or entries: Modbus TCP; EtherNet/IP and CIP; DNP3; BACnet/IP; OPC UA; IEC 60870-5-104; IEC 61850; PROFINET; and S7comm, which was the final protocol in the series.
Rank #3
- XMHZYMXFC Industrial-grade Logic Analyzer 400M Sampling Rate 16 Channels Supports PulseView
These protocols differ in architecture, transport, message structure, security mechanisms, and assumptions. The workflow helped me frame experiments across the series, but it did not make one experiment or result applicable to all of them. The series was about investigating protocol behavior, not ranking protocols or measuring their performance against one another.
What a controlled experiment can—and cannot—show
A result from a software-defined lab is evidence about the implementation and conditions I tested. It does not automatically establish how every vendor implementation behaves, or how a production industrial system is configured. A realistic-looking environment cannot reproduce every property of a deployed system; a deliberately small lab can still answer a narrow, useful question when its boundaries are clear.
Rank #4
- Compatibility: This DC power consumption meter seamlessly integrates with various systems requiring energy monitoring thanks to its standardized ModbusRTU protocol support The device ensures with industrial equipment solar setups and battery management systems while maintaining consistent data accuracy
- Performance: The watt meter delivers measurements for DC voltage current active power frequency and cumulative energy consumption Its circuitry captures real-time data with minimal deviation making it ideal for laboratories workshops and renewable energy projects
- Customization: Multiple shunt specifications allow this consumption analyzer to accommodate current ranges from 50A to 300A Users can select from ten preconfigured kits tailored for different load capacities ensuring optimal performance across diverse electrical applications
- : A robust UART-to-RS485 interface forms the physical layer of this DC amp meter with a fixed baud rate of 9600 8 data bits and 2 stop bits This stable connection protocol eliminates interference during extended in high-noise environments
- Functionality: Advanced ModbusRTU protocol implementation enables this energy to execute commands including 0x03 0x04 and 0x06 function codes The streamlined framework supports seamless integration with SCADA systems and IoT platforms
That distinction also changes how comparisons should be made. To understand what two experiments establish, look at the question each one asks, the implementation and lab boundaries, the packet evidence available, and how far the interpretation is being generalized. Similar-looking protocol names or setups are not enough to justify applying one result to another implementation.
How I would approach a protocol question now
- Define the claim or question before adding lab components.
- Build only enough of a controlled local environment to generate the interaction you need to inspect.
- Capture traffic when the claim concerns what crossed the wire.
- Mark the boundary between what the packets show and what you infer from them.
- Share scripts, notes, captures, and methods so other people can inspect or reproduce the experiment.
My repository contains research materials, including code, notes, and experiments. Sharing those materials makes the method more inspectable; it does not turn a result from one implementation into a universal protocol guarantee.
Best Value
- Supports both USBCAN2 and USBCAN_2E_U modes, switchable via the built-in button. DUAL-CHANNEL USB TO CAN INTERFACE
- CAN 2.0A AND CAN 2.0B SUPPORT – Works with standard and extended frames, data and remote frames, and bidirectional CAN transmission. Configurable baud rates range from 5Kbps to 1Mbps, with support for custom timing settings.
- INDUSTRIAL-GRADE ISOLATION – Each CAN channel uses an independent DC-DC power module and magnetic isolation. The isolated design provides up to 2500V/min isolation and helps improve resistance to electrical interference.
- HIGH-SPEED DATA PROCESSING – Features a 1,500-frame receive buffer and supports reception rates of up to 10,000 frames per second on each channel. USB-powered operation eliminates the need for a separate power adapter.
- SOFTWARE AND DEVELOPMENT SUPPORT – Use CANMonitor to configure channels, transmit and receive frames, filter CAN IDs, save data and perform playback. DLL, LIB, Visual C++ examples and interface functions support custom application development. A driver installation is required.
When I have to decide whether an experiment is ready, I return to the question that closed my retrospective: “What exactly do I want to establish, and what evidence do I need to establish it?” — RUGERO Tesla (404Saint).
This account reflects my own process and experience; it is not an independent evaluation of every experiment or implementation.
Quick Recap
Read my retrospective on DEV Community.
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