The Hidden Cost
A typical automotive plant runs OPC UA on newer equipment, OPC DA on legacy Windows-based SCADA systems, Modbus on legacy PLCs, Siemens S7 on a significant portion of the automation layer, and BACnet for building systems. Each protocol has its own data model, timing semantics, and addressing scheme.
Without a structured data plane, every system that needs this data must independently solve protocol translation, context mapping, and reliability. This is the fragmentation tax - a cost that compounds with every new integration.
Protocol Diversity in Practice
The problem is not that multiple protocols exist. The problem is how they are bridged.
Generic gateways flatten protocol-specific metadata into lowest-common-denominator formats. OPC UA quality indicators are lost. OPC DA item quality codes are discarded. Modbus register addresses are abstracted away. S7 data block context is discarded. The result: data that technically arrives at its destination but has lost the information needed to interpret it correctly.
Sparkplug B attempts to standardize the MQTT layer, but standardization at the broker does not solve fragmentation at the source. Data must be properly acquired and contextualized before it reaches any broker.
The Data Plane Alternative
A protocol-native data plane acquires data in each protocol's native semantics - preserving timestamps, quality indicators, and device-specific metadata. Structure and context are applied once, at the source, and every downstream system receives the same consistent representation.
The fragmentation tax drops to near zero. New protocols are added at the data plane. Downstream consumers are unaffected.