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.
HSR Frame Structure — How the HSR Tag Works
The HSR tag is six bytes — EtherType, PathId, LSDU size, and sequence number. Here's what each field does and why it matters for the ring to work.
HSR Node Modes Explained: H, N, T, M, U and X (IEC 62439-3)
A clear breakdown of all six HSR node modes — what each one does, when to use it, and what breaks if you get it wrong. Based on IEC 62439-3.
PTP Clock Synchronization in PRP and HSR Networks
How PTP works across PRP and HSR networks — BMCA, Hybrid Clocks, correctionField, RedBox clock roles, and what the standards actually require.
How HSR Ring Sizing Affects Latency
Node count, forwarding delay, and frame size all affect HSR ring latency. Learn how to calculate worst-case delay and size your ring for IEC 61850 applications.
How to Connect PRP and HSR Networks | Step-by-Step Guide (IEC 62439-3)
How to connect PRP and HSR networks using RedBox and QuadBox. Five topology scenarios with step-by-step guidance, IP example, and rules from IEC 62439-3.
RedBox and QuadBox in PRP/HSR Networks
RedBox connects legacy devices to PRP and HSR networks. QuadBox links two HSR rings. Here's how both work, when to use them, and what the standard actually says.
PRP vs HSR Explained: IEC 62439-3 Complete Guide to Redundant Industrial Networks
Learn the key differences between PRP and HSR under IEC 62439-3. Clear guide to redundancy behavior, performance, and how to interconnect both systems.
HSR (High-Availability Seamless Redundancy) in IEC 61850 Networks: Complete Technical Guide
Deep technical guide to HSR for IEC 61850 networks. Learn how HSR frames, nodes, forwarding, RedBoxes, and QuadBoxes deliver zero-time redundancy.