300+ SCADA Protocol Articles & Guides
Deep dives on Modbus, DNP3, IEC 60870-5-101/104, IEC 61850, OPC UA, Profinet, MQTT, IEC 62443, and substation automation — written for practicing engineers.
CIP Path Segments Explained: EPATH Encoding for Engineers
Complete guide to CIP path segments: Port, Logical, Network, Symbolic, Data segments. Decode 20 04 24 66, EPATH format, Electronic Key segment, padded vs packed.
CIP Connection Manager Object Explained (Class 0x06)
CIP Connection Manager Object (Class 0x06): the object behind Forward_Open. Services, attributes, counters, Network Connection Parameters, error codes.
CIP Ethernet Link Object Explained (Class 0xF6)
Complete CIP Ethernet Link Object reference (Class 0xF6): Interface Flags, MAC address, link speed, RFC 1213/1643 counters, multi-port DLR diagnostics.
CIP TCP/IP Interface Object Explained (Class 0xF5)
Complete guide to CIP TCP/IP Interface Object (Class 0xF5): IP address, subnet mask, gateway, DNS, DHCP/BOOTP, multicast configuration, TTL, attributes.
CIP Connection Types Explained: Transport Class 0, 1, 2, and 3
Complete guide to CIP transport classes: Class 0, 1, 2, 3 connection types, the Transport Class Trigger byte, production triggers, and Forward_Open encoding.
CIP Assembly Object Explained: How EtherNet/IP Devices Bundle I/O Data
How the CIP Assembly Object works in EtherNet/IP: input and output assemblies, instance attributes, and how the data maps into an I/O connection.
CIP Forward_Open Service Explained: How Every EtherNet/IP Connection Starts
Complete guide to the CIP Forward_Open service: request structure, network connection parameters, transport class, electronic keying, and Extended Status.
CIP Data Types Complete Reference: Elementary, String, Time, and Structured Types
Complete reference of CIP data types: BOOL, SINT, INT, DINT, REAL, STRING, EPATH, structured types, type codes, sizes, ranges, and encoding rules.
CIP General Status Codes Reference: Complete List with Troubleshooting
Complete reference of CIP General Status Codes 0x00 through 0x2B with descriptions, common causes, and troubleshooting steps for every code.
CIP Service Codes Complete Reference: Common Services and Object-Specific Codes
Complete reference of CIP service codes: Get_Attribute_Single, Set_Attribute_Single, Forward_Open, Multiple_Service_Packet, and all common services.
EtherNet/IP Encapsulation Protocol Explained: The 24-Byte Header That Carries CIP
How EtherNet/IP wraps CIP onto TCP/IP: the 24-byte encapsulation header, commands, session management, Common Packet Format, and status codes.
EtherCAT Protocol Explained: The Trick That Makes It Fast
EtherCAT protocol explained end to end: processing on the fly, logical addressing and FMMU, frame and datagram structure, four addressing modes, Distributed Clocks, slave internals (FMMU, sync managers, SII), mailbox protocols, over-UDP/IP variant, and the state machine.
Wireshark EtherNet/IP: Decode CIP Traffic
Wireshark EtherNet/IP capture and decode: CIP services, Forward_Open on TCP 44818, implicit I/O on UDP 2222, status codes, and connection troubleshooting.
Wireshark OPC UA: Decode Client/Server Traffic
Wireshark OPC UA capture and decode: display filters, service node IDs, session and channel setup, decrypting secured traffic, and certificate failures.
Wireshark PROFINET: Decode RT, DCP, and IO Traffic
Wireshark PROFINET capture and decode: RT cyclic frames, DCP discovery, connection setup, alarm frames, LLDP topology checks, and cycle-time troubleshooting.
Wireshark IEC 104: Decode IEC 60870-5-104 Traffic
Wireshark IEC 104 decoding on TCP 2404: I, S, and U frame types, ASDU type IDs, cause of transmission values, CP56Time2a timestamps, and SPAN capture setup.