PLC Programming
.io

OPC-UA

Open Platform Communications Unified Architecture - platform-independent standard for industrial communication and data exchange.

Type: Industrial EthernetSpeed: Network dependentReleased: 2008Organization: OPC Foundation
Network dependent
Bandwidth
Unlimited
Max Nodes
Network dependent
Max Distance
No
Real-Time

Protocol Overview

Open Platform Communications Unified Architecture - platform-independent standard for industrial communication and data exchange.

When to Use OPC-UA

Choose OPC-UA for enterprise integration, cloud connectivity, multi-vendor environments, or Industry 4.0 initiatives requiring secure data exchange.

Technical Specifications

Physical Layer

  • Physical Layer: IP-based
  • Cable Type: Any IP network media
  • Topology: Any IP network topology
  • Power Over Cable: No

Data Layer

  • Data Link: TCP/IP or SOAP/HTTPS
  • Encoding: Binary or XML
  • Error Detection: Built-in security
  • Frame Size: Network dependent

Performance

  • Scan Time: Configurable subscription rates
  • Deterministic: No
  • Real-Time: No

Certification

  • Certification Required: No
  • License Cost: Open source implementations available, commercial stacks vary
  • Version: 1.05

Advantages & Disadvantages

Advantages

  • ✓Platform and vendor independent
  • ✓Built-in security (encryption, authentication)
  • ✓Rich information modeling
  • ✓Works across firewalls
  • ✓Supports complex data structures
  • ✓Historical data access
  • ✓Pub/sub and client/server models
  • ✓Industry 4.0 and IoT ready

Disadvantages

  • ✗Not designed for hard real-time
  • ✗Higher complexity than traditional protocols
  • ✗More computing resources required
  • ✗Learning curve for information modeling
  • ✗Overhead for simple applications

Common Use Cases & Applications

Enterprise system integration
MES/ERP connectivity
Cloud and IoT applications
Cross-platform data exchange
Industry 4.0 implementations
Historian integration
Multi-vendor system integration

Industry Adoption

Adoption LevelHigh and growing rapidly
Market ShareGrowing rapidly as Industry 4.0 standard
Geographic PresenceWorldwide
Primary Industries
All industriesParticularly strong in Process IndustriesPharmaceuticalsDiscrete Manufacturing

Supported Message Types

Read
Write
Subscribe
Method calls
Events
Historical access

Supported PLC Brands

SiemensAllen-BradleySchneider ElectricABBBeckhoff
B&R
Mitsubishi
Omron

Quick Links

Alternative Protocols

Related Standards

  • IEC 61131-3

    International standard for programmable logic controller programming languages. Defines 5 programmin...

  • IEC 61131 Series

    Complete series of international standards for programmable logic controllers covering hardware, sof...

  • IEC 61499

    Standard for distributed control systems using function blocks. Designed for Industry 4.0 and distri...

  • ISA-95

    Enterprise-control system integration standard. Defines interface between enterprise systems (ERP/ME...

Related Protocols