27 IoT & Wireless questions from the Embedded Systems bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
B.Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
C.low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors
D.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
2. Which term means: "low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors"?
Junior
A.Cellular modem AT commands
B.Zigbee
C.BLE
D.Device provisioning
Answer + AI explanation with Pro
3. Which statement is correct?
Junior
A.BLE — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
B.BLE — securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
C.BLE — Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
D.BLE — low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors
Answer + AI explanation with Pro
4. What is MQTT?
Junior
A.lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
B.text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
C.RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
D.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
5. Which term means: "lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport"?
Junior
A.MQTT
B.Cellular modem AT commands
C.Device provisioning
D.NB-IoT and LTE-M
Answer + AI explanation with Pro
6. Which statement is correct?
Junior
A.MQTT — long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
B.MQTT — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
C.MQTT — lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
D.MQTT — IEEE 802.15.4 mesh at 2.4 GHz with coordinator, routers and end devices, at 250 kbit/s suited to lighting and sensor networks
Answer + AI explanation with Pro
7. What is LoRaWAN?
Junior
A.RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
B.low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors
C.long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
D.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
8. Which term means: "long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join"?
Junior
A.LoRaWAN
B.Cellular modem AT commands
C.MQTT
D.CoAP
Answer + AI explanation with Pro
9. Which statement is correct?
Junior
A.LoRaWAN — text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
B.LoRaWAN — securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
C.LoRaWAN — long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
D.LoRaWAN — 3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
10. What is Zigbee?
Mid
A.IEEE 802.15.4 mesh at 2.4 GHz with coordinator, routers and end devices, at 250 kbit/s suited to lighting and sensor networks
B.text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
C.lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
D.securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
Answer + AI explanation with Pro
11. Which term means: "IEEE 802.15.4 mesh at 2.4 GHz with coordinator, routers and end devices, at 250 kbit/s suited to lighting and sensor networks"?
Mid
A.MQTT
B.CoAP
C.Cellular modem AT commands
D.Zigbee
Answer + AI explanation with Pro
12. Which statement is correct?
Mid
A.Zigbee — IEEE 802.15.4 mesh at 2.4 GHz with coordinator, routers and end devices, at 250 kbit/s suited to lighting and sensor networks
B.Zigbee — text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
C.Zigbee — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
D.Zigbee — 3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
13. What is Thread and Matter?
Mid
A.securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
B.lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
C.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
D.Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
Answer + AI explanation with Pro
14. Which term means: "Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices"?
Mid
A.Cellular modem AT commands
B.NB-IoT and LTE-M
C.BLE
D.Thread and Matter
Answer + AI explanation with Pro
15. Which statement is correct?
Mid
A.Thread and Matter — text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
B.Thread and Matter — long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
C.Thread and Matter — securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
D.Thread and Matter — Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
Answer + AI explanation with Pro
16. What is CoAP?
Mid
A.long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
B.RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
C.text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
D.low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors
Answer + AI explanation with Pro
17. Which term means: "RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS"?
Mid
A.CoAP
B.LoRaWAN
C.BLE
D.Device provisioning
Answer + AI explanation with Pro
18. Which statement is correct?
Mid
A.CoAP — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
B.CoAP — text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
C.CoAP — IEEE 802.15.4 mesh at 2.4 GHz with coordinator, routers and end devices, at 250 kbit/s suited to lighting and sensor networks
D.CoAP — 3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
19. What is NB-IoT and LTE-M?
Mid
A.Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
B.low-energy 2.4 GHz radio with 40 channels, advertising and connection events and GATT services and characteristics, averaging microamps for battery sensors
C.text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
D.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
20. Which term means: "3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life"?
Mid
A.Cellular modem AT commands
B.NB-IoT and LTE-M
C.CoAP
D.Zigbee
Answer + AI explanation with Pro
21. Which statement is correct?
Mid
A.NB-IoT and LTE-M — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
B.NB-IoT and LTE-M — lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
C.NB-IoT and LTE-M — 3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
D.NB-IoT and LTE-M — long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
Answer + AI explanation with Pro
22. What is Cellular modem AT commands?
Mid
A.RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
B.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
C.securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
D.text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
Answer + AI explanation with Pro
23. Which term means: "text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously"?
Mid
A.Cellular modem AT commands
B.LoRaWAN
C.Zigbee
D.NB-IoT and LTE-M
Answer + AI explanation with Pro
24. Which statement is correct?
Mid
A.Cellular modem AT commands — long-range low-power WAN on sub-GHz ISM bands (865–867 MHz in India) using chirp spread spectrum, with device classes A, B and C and OTAA or ABP join
B.Cellular modem AT commands — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
C.Cellular modem AT commands — Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
D.Cellular modem AT commands — text commands such as AT+CREG, AT+CGATT and AT+CSQ over UART to register, attach and open sockets, with an unsolicited result stream the firmware must parse asynchronously
Answer + AI explanation with Pro
25. What is Device provisioning?
Senior
A.lightweight publish-subscribe protocol over TCP with a broker, topics, three QoS levels and retained and last-will messages, the default IoT telemetry transport
B.Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
C.securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
D.3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
Answer + AI explanation with Pro
26. Which term means: "securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates"?
Senior
A.NB-IoT and LTE-M
B.Cellular modem AT commands
C.Device provisioning
D.BLE
Answer + AI explanation with Pro
27. Which statement is correct?
Senior
A.Device provisioning — 3GPP cellular IoT categories: NB-IoT for very low data rate and deep coverage, LTE-M (Cat-M1) for higher throughput and mobility, both using PSM and eDRX for battery life
B.Device provisioning — RESTful UDP protocol with GET, PUT, POST, DELETE and observe, designed for constrained devices, mappable to HTTP and secured with DTLS
C.Device provisioning — securely giving each unit a unique identity and credentials such as certificates or keys at manufacture or first boot, for example fleet provisioning with claim certificates
D.Device provisioning — Thread is an IPv6 mesh over 802.15.4; Matter is the application-layer standard running over Thread, Wi-Fi and Ethernet for interoperable smart-home devices
Answer + AI explanation with Pro
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