Category Archives: Wireshark Tutorials

Wireshark tutorials for Industrial protocols including Modbus, DNP3, IEC 61850, OPC UA, and industrial network troubleshooting. Analyze, decode, and diagnose packets easily.

Wireshark for EtherNet/IP: How to Capture and Decode CIP Traffic

EtherNet/IP (Ethernet Industrial Protocol) is the leading industrial Ethernet protocol in North America. It carries CIP (Common Industrial Protocol) messages over standard TCP/IP and UDP/IP. Wireshark fully decodes EtherNet/IP using two dissectors: EtherNet/IP uses two ports: This guide covers how to capture both traffic types, which display filters to use, how to decode CIP services and I/O connections,… Read More: Wireshark for EtherNet/IP: How to Capture and Decode CIP Traffic »

Wireshark for Modbus RTU: How to Capture and Decode Serial RS-485 Traffic

Wireshark is known as an Ethernet protocol analyzer. But it can also capture Modbus RTU traffic over RS-485 serial links — using a free extension called WiresharkSerialAdapter. This is not a built-in feature. Wireshark does not natively capture from COM ports. You need a USB-to-RS-485 adapter connected to the bus as a passive listener, plus the WiresharkSerialAdapter extension… Read More: Wireshark for Modbus RTU: How to Capture and Decode Serial… »

How to Decrypt Encrypted Industrial Protocol Traffic in Wireshark

Industrial protocols are moving to TLS encryption. Modbus/TCP Security uses port 802. IEC 60870-5-104 over TLS uses port 19998. IEC 61850 MMS over TLS uses port 3782. OPC UA encrypts at the application layer. When encryption is enabled, Wireshark shows “Application Data” instead of decoded protocol fields. You can see that packets are flowing, but you cannot read… Read More: How to Decrypt Encrypted Industrial Protocol Traffic in Wireshark »

Wireshark for PROFINET: How to Capture and Decode RT, DCP, and IO Traffic

PROFINET traffic does not use TCP/IP for cyclic I/O data. It runs directly on Ethernet Layer 2 with EtherType 0x8892. This means you cannot capture it with a TCP port filter — you need to capture all Ethernet traffic on the interface and then filter in Wireshark. Wireshark fully decodes PROFINET using several dissectors: This guide covers how… Read More: Wireshark for PROFINET: How to Capture and Decode RT, DCP,… »

Wireshark for MQTT: How to Capture and Decode Industrial IoT Traffic

MQTT (MQ Telemetry Transport) is the most widely used protocol in industrial IoT. It connects sensors, PLCs, gateways, and edge devices to cloud platforms and SCADA historians using a lightweight publish/subscribe model over TCP. Wireshark fully decodes MQTT — every CONNECT, PUBLISH, SUBSCRIBE, and DISCONNECT message, including topic names, QoS levels, payloads, and client IDs — all in… Read More: Wireshark for MQTT: How to Capture and Decode Industrial IoT… »

Wireshark for OPC UA: How to Capture and Decode Client/Server Traffic

OPC UA (Unified Architecture) is the leading platform-independent protocol for industrial data exchange. It connects SCADA systems, MES platforms, HMI panels, historians, and cloud gateways to PLCs, DCS controllers, and edge devices. OPC UA uses the OPC Binary protocol over TCP on port 4840 (IANA registered as “opc.tcp”). Wireshark decodes every OPC UA service — OpenSecureChannel, CreateSession, Browse,… Read More: Wireshark for OPC UA: How to Capture and Decode Client/Server… »

Wireshark for DNP3: How to Capture, Filter, and Troubleshoot

DNP3 (Distributed Network Protocol 3.0) is the dominant SCADA protocol in North America for electric utilities, water systems, and oil and gas. It runs over TCP or UDP on port 20000. Wireshark fully decodes DNP3 — data link layer, transport layer, and application layer. You can see every function code, object group, data point index, quality flag, and… Read More: Wireshark for DNP3: How to Capture, Filter, and Troubleshoot »

Wireshark for Modbus TCP: How to Capture, Filter, and Troubleshoot

Modbus TCP is one of the easiest protocols to analyze in Wireshark. It runs on TCP port 502, uses a simple request/response pattern, and Wireshark decodes every field — MBAP header, function code, register addresses, and data values — in plain text. But engineers still struggle with three things: finding the right display filters, understanding what a healthy… Read More: Wireshark for Modbus TCP: How to Capture, Filter, and Troubleshoot »

Wireshark for IEC 61850 MMS: How to Capture and Decode Client/Server Traffic

MMS (Manufacturing Message Specification) is the client/server protocol used by IEC 61850 for SCADA communication, reporting, control commands, and engineering access. It runs over TCP port 102. When an IED stops reporting to SCADA, when a control command fails, or when an MMS association does not establish — Wireshark is the first tool you reach for. But decoding… Read More: Wireshark for IEC 61850 MMS: How to Capture and Decode… »