Which messaging protocol uses a Publish/Subscribe pattern over TCP/IP and is widely adopted for lightweight IoT telemetry?
MQTT is an extremely lightweight publish/subscribe messaging protocol designed for constrained devices and bandwidth-limited networks.
Which IoT protocol operates over UDP, follows a RESTful Request/Response architecture similar to HTTP, and is standardized in RFC 7252?
CoAP (Constrained Application Protocol) is a web transfer protocol designed for constrained nodes and networks, running over UDP to reduce header overhead.
In Zigbee network topology, which device type acts as the root of the network tree, starts the network, and stores network keys?
There is exactly one Zigbee Coordinator (ZC) per network. It initiates the network, selects the radio channel, sets up security, and manages child nodes.
In Zigbee networks, which low-power node type cannot route traffic for other nodes and can sleep most of the time to preserve battery life?
Zigbee End Devices (ZED) talk only to their parent router/coordinator, do not route data, and enter deep sleep states to achieve years of battery lifetime.
Which encryption standard is mandated at the security layer of IEEE 802.15.4 and Zigbee protocols for data confidentiality and integrity?
IEEE 802.15.4 and Zigbee protocols mandate symmetric key AES-128 encryption with CCM* mode for message integrity, authentication, and privacy.