Which low-power wide-area network (LPWAN) protocol technology uses Chirp Spread Spectrum (CSS) modulation to achieve long communication ranges (up to 15 km)?
LoRa (Long Range) employs Chirp Spread Spectrum (CSS) radio modulation to transmit data across miles with low power consumption.
In MQTT QoS (Quality of Service) levels, which QoS level guarantees 'Exactly Once' message delivery through a 4-step handshake?
MQTT QoS 2 guarantees 'Exactly Once' delivery using 4 packets: PUBLISH, PUBREC, PUBREL, and PUBCOMP.
Which short-range protocol operating at 13.56 MHz is an extension of RFID used for contactless payments and peer-to-peer data sharing?
Near Field Communication (NFC) operates at 13.56 MHz within a distance of ~4 cm, built upon ISO/IEC 14443 RFID standards.
Which Bluetooth version introduced Bluetooth Low Energy (BLE) / Smart for ultra-low power IoT application nodes?
Bluetooth 4.0 specification (2010) introduced Bluetooth Low Energy (BLE), enabling sensor operations powered by coin-cell batteries.
What is the primary function of an RTU (Remote Terminal Unit) in a SCADA industrial network?
An RTU (Remote Terminal Unit) interfaces directly with physical sensors/actuators in industrial sites and transmits telemetry to the central SCADA master unit.