Why CoAP simulation matters
Constrained IoT devices use CoAP (Constrained Application Protocol) to exchange data over UDP with minimal overhead. Integration testing against real constrained devices is difficult because hardware is often prototype-stage, network conditions vary, and LwM2M/CoAP stacks behave differently across implementations.
SPX closes that gap by simulating CoAP server endpoints with realistic resource trees, observable attributes, and deterministic responses. Teams can validate IoT clients, LwM2M integrations, and constrained device behavior without waiting on hardware.
Constrained devices are prototype-stage and hard to test
CoAP resource trees and observe patterns need validation
UDP exchanges and resource state are hard to inspect
Simulate CoAP servers with controllable resources
What SPX simulates
SPX provides a CoAP server adapter (coap_server) that exposes resources over UDP and maps requests onto twin attributes using resource and binding definitions. The adapter supports GET, PUT, and observe methods.
Resource trees with GET, PUT, and observe
Works with LwM2M device models
Change resource values and observe behavior at runtime
Reproducible constrained device scenarios
Core capabilities
CoAP simulation in SPX is designed for IoT integration testing, embedded firmware validation, and LwM2M stack verification.
Map CoAP resources to twin attributes
Steer sensor values and observe behavior
Run CoAP integration tests in Docker
Inspect CoAP requests and resource state
Example models
SPX ships with CoAP-compatible environment sensor models that work with LwM2M stacks and raw CoAP clients.
LwM2M Environment Sensor (CoAP)
Embedded & Lab Pack
Model Catalog
Developer path
CoAP simulation connects directly to the model catalog, Embedded & Lab Pack, and IoT workflows.