Communication & IoT

IoT reference model (devices, gateway, edge, cloud), Wireless communication principles (modulation, spectrum, bandwidth), Short-range protocols (Bluetooth LE, Zigbee, Z-Wave), LPWAN technologies (LoRaWAN, NB-IoT, LTE-M, Sigfox), Frequency bands and regulatory domains, Power consumption models and duty cycle constraints, Network topologies (star, mesh, tree).

MQTT protocol (QoS levels, retained messages, last will), CoAP for constrained devices (DTLS security, observe pattern), HTTP/2 and WebSockets for IoT, AMQP and STOMP messaging, DDS for robotics real-time communication, Protocol benchmarking (overhead, latency, throughput), Header compression techniques (6LoWPAN).

Device authentication (X.509 certificates, pre-shared keys, token-based), Secure communication (TLS/DTLS, mbedTLS), Firmware Over-The-Air (OTA) updates, Device lifecycle management (provisioning, decommissioning), Secure boot and attestation, Key management in constrained environments, Zero-touch provisioning (ZTP).

Edge vs. cloud computing trade-offs, Gateway patterns (protocol translation, data aggregation, local processing), EdgeX Foundry and Eclipse IoT frameworks, Time-Sensitive Networking (TSN) for industrial IoT, Containerized edge computing (K3s, microk8s), Data preprocessing at edge (filtering, transformation, analytics).

AWS IoT Core (Greengrass, Device Shadow), Azure IoT Hub (Device Twin, DPS), Google Cloud IoT (Cloud IoT Edge), ROS2 DDS integration with IoT protocols, Multi-protocol gateways for robotics fleets, Digital twins and simulation-in-the-loop, Industrial IoT protocols (OPC UA, Modbus TCP, PROFINET).