Page History

1. The Problem

Challenge: Operate and observe hundreds of distributed midstream sites with PLCs and intermittent, bandwidth-limited links—while keeping on-site autonomy and ensuring a unified, secure, and scalable publish/subscribe model for corporate operations, analytics, and alarms.

Specific pain points:

• Multiprotocol collection (ControlLogix + DF1) into a single publish model without custom middleware.

• Reliable delivery over satellite with high latency/jitter and strict bandwidth budgets.

• Broker high-availability and end-to-end observability at scale (350 sites, 500k+ tags).

• Simple, repeatable deployment on router-class Linux hardware with unattended recovery.

Impact: Without a standardized, resilient gateway + MQTT pattern, sites face delayed event visibility, manual correlation, higher truck-rolls, and longer MTTR during incidents.

Example: “Prior to MQTT + EdgeConnect, engineers had to manually pull logs from PLCs after outages; post-event diagnostics stretched MTTR and risked SLA breaches.”

2. The Solution

2.1 Overview

...

[PLC Layer: ControlLogix / DF1]           [Edge Layer: Per-Site Gateway]                [Network Layer]
  • CIP/EtherNet/IP (CLX)                   • FrameworX (EdgeConnect on Linux)         • MQTT brokers (HA, N=4)
  • DF1 (serial)                            • Poll ? Buffer ? Publish                  • Subscribers: Third-Party brokers consumers
                                            • Watchdog, AutoStart                      

   ????TCP/IP ???????????????????????????????  Router  ???????????????????????????????????  Broker

[PLC Layer: ControlLogix / DF1] [Edge Layer: Per-Site Gateway] [Network Layer] • CIP/EtherNet/IP (CLX) • FrameworX (EdgeConnect on Linux) • MQTT brokers (HA, N=4) • DF1 (serial) • Poll → Buffer → Publish • Subscribers: Third-Party brokers consumers • Watchdog, AutoStart ????TCP/IP ??????????????????????????????? Router ??????????????????????????????????? Broker

2.3 Topology

2.4 Network Architecture

• Segmented per site VLANs; secure egress to broker endpoints only.

• Backpressure control: publish rate limiting, payload compression, delta/exception reporting.

...

• Multiprotocol edge collection (ControlLogix + DF1) with a unified MQTT/Sparkplug output.

• Router-grade Linux runtime enabling low footprint deployment close to the PLCs.

• Store-and-Forward + AutoStart + Watchdog for unattended resilience over satellite.

• Broker HA (N=4) and access governance to prevent network overflow and ensure continuity.

• Real-time broker/edge monitoring with alarms on heartbeat loss, queue growth, or reconnect storms.

Why it’s non-trivial elsewhere: The combination of CIP + DF1 ingestion, Sparkplug governance at scale, true edge resilience over high-latency links, and 4-node broker HA across 350 sites typically requires significant custom engineering; EdgeConnect standardizes it.

4. The Results

• Reduced MTTR by 70%: Eliminated manual log collection from PLCs post-outage through real-time MQTT telemetry, enabling immediate incident visibility and faster root cause analysis.

• Achieved 99.5% uptime across 350 sites: 4-node broker HA cluster with store-and-forward edge resilience maintained continuous operations despite satellite link interruptions and bandwidth constraints.

• Standardized deployment at scale: Single EdgeConnect solution replaced custom middleware across all sites, reducing deployment complexity and enabling consistent 500k+ tag collection from mixed ControlLogix/DF1 environments.

• Enhanced operational visibility: Real-time publish/subscribe model with Sparkplug B provided enterprise-wide monitoring and analytics capabilities, replacing reactive maintenance with proactive incident management.