What is CoAP protocol IoT | CoAP Architecture,message format
Connect devices to IoT Platform over CoAP
GitHub - chkr1011/CoAPnet: CoAPnet is a high performance .NET library for CoAP based communication. It provides a CoAP client and a CoAP server. It also has DTLS support out of the box.
Getting started with CoAP development - Zigbee & Thread forum - Zigbee & Thread - TI E2E support forums