-: IMPORTANT NOTICE :-
1. State whether the following statement is true or false.
Statement: Wired HART lacks a network layer.
a. True
b. False
Explanation:
Wired HART (Highway Addressable Remote Transducer) is a widely used industrial communication protocol. It is a master-slave communication protocol that operates on the physical layer of the OSI model. However, it does not include a separate network layer. The HART protocol is designed to work over the same wires that carry the 4-20mA analog signal, so it operates at the physical and data link layers of the OSI model. It does not have a distinct network layer like some other communication protocols.
2. The HART physical layer is derived from ____________ protocol and operates only in __________ GHz ISM band.
a. IEEE 802.15.4, 2.4
b. IEEE 802.15.4, 4.8
c. IEEE 802.16.5, 4.8
d. None of these
Explanation:
HART (Highway Addressable Remote Transducer) is a communication protocol commonly used in industrial automation and control systems. The HART physical layer is indeed derived from the IEEE 802.15.4 protocol, which is a standard for low-rate wireless personal area networks (WPANs). The HART protocol operates in the 2.4 GHz ISM (Industrial, Scientific, and Medical) band, allowing for wireless communication between devices in industrial settings. This frequency band is widely used for various wireless communication technologies due to its availability and suitability for short-range applications.
3. State whether the following statement is True or False
Statement: Super-frames in HART consist of grouped 20ms wide timeslots.
a. True
b. False
Explanation:
Super-frames in HART (Highway Addressable Remote Transducer) communication protocol consist of grouped 82.667 ms wide time slots, not 20ms wide. HART uses a combination of frequency shift keying (FSK) and time-division multiplexing to enable communication between field devices and a control system. Each super-frame is divided into a series of time slots, which are used for various types of communication between the master device and the field devices.
4. _________________ identifies channels consistently affected by interference and removes them from use.
a. Channel hopping
b. Channel aggregating
c. Channel blacklisting
d. Frequency aggregating
Explanation:
Channel blacklisting is a technique used in wireless communication protocols to identify channels that are consistently affected by interference or poor signal quality and then remove those channels from use. This helps improve the overall reliability and performance of the wireless communication system by avoiding channels that are prone to issues. The system can then focus on using the remaining channels that provide better communication quality.
5. The _________________ supervises each node in the network and guides them on when and where to send packets.
a. Application manager
b. Network manager
c. Trust manager
d. None of these
Explanation:
The network manager is responsible for supervising each node in a network and providing guidance on various aspects of network communication. This includes tasks such as managing network topology, assigning addresses, coordinating communication schedules, handling routing decisions, and determining when and where nodes should send packets. The network manager plays a crucial role in maintaining the overall efficiency and functionality of the network.
6. NFC is designed for use by devices within _________ to each other?
a. Close proximity
b. No near contact
c. Both (a) and (b)
d. None of these
Explanation:
NFC (Near Field Communication) is a wireless communication technology designed for devices to communicate with each other when they are in close proximity or physical contact. NFC operates over short distances, typically within a few centimeters, making it suitable for applications like contactless payments, data transfer between devices, and access control systems.
7. ______________ contain information which is readable by other devices, however it cannot read information itself.
a. Active NFC devices
b. Dumb NFC devices
c. Passive NFC devices
d. None of these
Explanation:
Passive NFC devices are those that can be read by other devices, such as smartphones or NFC readers, but they do not have the capability to initiate communication or read information from other devices on their own. These devices rely on an active NFC device, such as a smartphone, to provide the necessary energy and communication capabilities for interaction. Passive NFC devices are often used in applications like contactless payment cards, smart posters, and NFC tags.
8. NFC devices work on the principle of ___________________?
a. Magnetic introduction
b. Magnetic induction
c. Both (a) and (b)
d. None of these
Explanation:
NFC (Near Field Communication) devices work on the principle of magnetic induction. Magnetic induction involves creating a magnetic field that can induce a current in nearby conductive materials. NFC devices use this principle to communicate by generating magnetic fields that are detected by other NFC devices in close proximity. This allows for the exchange of data and information between devices without the need for physical contact.
9. Which of these is NOT a mode of operation NFC?
a. Server-to-Server
b. Peer-to-Peer
c. Read/Write
d. Card emulation
Explanation:
NFC (Near Field Communication) technology supports several modes of operation, including:
- Peer-to-Peer: Two NFC-enabled devices communicate with each other, allowing data exchange and interaction.
- Read/Write: An active NFC device (like a smartphone) reads information from or writes information to a passive NFC device (like a tag).
- Card Emulation: An NFC-enabled device can emulate an NFC card, allowing it to be used for contactless payments or access control.
"Server-to-Server" is not a recognized mode of operation for NFC. NFC primarily involves communication between devices or between a device and a passive tag, rather than direct server-to-server communication.
10. State whether the following statement is true or false
Statement: Paging in Bluetooth is the process of forming a connection between two Bluetooth devices.
a. True
b. False
Explanation:
Paging in Bluetooth refers to the process by which one Bluetooth device initiates the establishment of a connection with another Bluetooth device. It's essentially the act of searching for and sending connection requests to discoverable devices. When one device wants to establish a connection with another device, it sends out a paging message to the target device's Bluetooth address. If the target device is in discoverable mode, it will respond, and a connection can be established. So, the statement is actually true, not false.
11. There are ______ modes of operation in Bluetooth.
a. 3
b. 4
c. 5
d. None of these
Explanation:
There are three primary modes of operation in Bluetooth:
1. **Discoverable Mode:** In this mode, a Bluetooth device actively broadcasts its presence, allowing other devices to find and connect to it.
2. **Connectable Mode:** This mode allows a device to accept incoming connection requests from other devices. It's used when a device is willing to establish new connections.
3. **Non-Discoverable and Non-Connectable Mode:** In this mode, a device is neither broadcasting its presence nor accepting incoming connections. This mode is often used to save power or maintain privacy.
So, there are three modes of operation in Bluetooth.
12. Zwave uses __________ for signaling and control?
a. Light
b. RF
c. Sound
d. None of these
Explanation:
Z-Wave is a wireless communication protocol designed primarily for home automation and control systems. It uses RF (Radio Frequency) signals to establish communication and control between devices. Z-Wave devices communicate using low-power RF signals in the sub-1 GHz frequency range, typically around 900 MHz. This frequency range offers good range and penetration capabilities, making it suitable for home environments where devices might be spread across different rooms or floors.
13. Which of the following is/are not a constraint on sensor nodes?
a. Must consume high power
b. Not be adaptive to the environment
c. Both (a) and (b)
d. None of these
Explanation:
Both options (a) and (b) are not constraints on sensor nodes. In reality, sensor nodes often have the constraint of needing to consume low power due to their reliance on batteries or energy harvesting. Additionally, being adaptive to the environment is a desirable feature for sensor nodes, allowing them to respond effectively to changes in the environment they are monitoring. Therefore, option (c) is the correct answer as it states that neither of these constraints applies to sensor nodes.
14. ___________ are simply those that are unable to perform an operation; this could be because of power failure and environmental events.
a. Normal nodes
b. Failed nodes
c. Badly failed nodes
d. None of these
Explanation:
Failed nodes are nodes within a network that are unable to perform their intended operations. This can occur due to various reasons, such as power failure, hardware malfunctions, or environmental events. Failed nodes are essentially nodes that are non-functional or not responding as expected within the network.
15. Dumb behavior of sensor nodes is _______________ in nature (as it is dependent on the effects of the environmental conditions).
a. Temporal
b. Spatial
c. Both (a) and (b)
d. None of these
Explanation:
The "dumb behavior" of sensor nodes, which is dependent on the effects of environmental conditions, is primarily related to the temporal nature of their behavior. Temporal refers to the aspect of time and how sensor nodes react or respond to changes in environmental conditions over time. The behavior of sensor nodes can change based on various temporal factors, such as changes in temperature, light, humidity, etc., which influence their readings and actions.