1.
Sensor Network is
Correct Answer
A. Heterogeneous system consisting of tiny sensors.
Explanation
The correct answer is "Heterogeneous system consisting of tiny sensors." This is because a sensor network refers to a system that consists of small, specialized sensors that are designed to collect and transmit data. These sensors can vary in terms of their capabilities, power, and communication protocols, hence making the network heterogeneous. The other options, such as a homogeneous system used in wireless or being very important for security, do not fully capture the essence of a sensor network.
2.
Challenges in wireless sensor networks are
Correct Answer
D. Both b and c.
Explanation
The challenges in wireless sensor networks include node mobility and self-configuring. Node mobility refers to the movement of sensor nodes, which can cause changes in network topology and affect data transmission. Self-configuring refers to the ability of sensor nodes to automatically adapt and configure themselves to changing network conditions. Therefore, the correct answer is both b and c.
3.
Devices may be “always on” or “low duty cycle” in
Correct Answer
C. Wireless sensors and Body area networks.
Explanation
The correct answer is "Wireless sensors and Body area networks." This is because both WiMAX and WCDMA, as well as HSDPA and HSUPA, can be classified as wireless communication technologies. However, these technologies are not specifically associated with being "always on" or "low duty cycle." On the other hand, wireless sensors and body area networks are specifically designed to operate in low power modes, making them suitable for "low duty cycle" applications. Therefore, the correct answer is "Wireless sensors and Body area networks."
4.
Grid’s Location Service (GLS) uses
Correct Answer
B. Distributed location servers.
Explanation
GLS uses distributed location servers. This means that the location information is stored and managed across multiple servers, rather than being centralized in one location. This allows for greater scalability and reliability, as the load can be distributed among the servers and there is no single point of failure. Additionally, distributed location servers enable faster retrieval of location information, as the request can be processed by the server closest to the user's location.
5.
RF signal strength is used
Correct Answer
B. To measure distance.
Explanation
The correct answer is "To measure distance." RF signal strength is commonly used to measure the distance between two points in wireless communication. By analyzing the strength of the signal, it is possible to estimate the distance between the transmitter and receiver. This information is crucial in various applications, such as determining the range of a wireless network or locating a device based on signal strength.
6.
Ideal positioning technique is
Correct Answer
D. All above.
Explanation
The ideal positioning technique is a combination of all the mentioned methods. By measuring the distance between the device and multiple known points, the position can be determined accurately through trilateration. Additionally, checking the signal strength can help in refining the positioning information. Therefore, using all the mentioned techniques together provides the most precise and reliable positioning results.
7.
WSN opportunities are in
Correct Answer
D. All above.
Explanation
The correct answer is "All above". This means that the opportunities for Wireless Sensor Networks (WSN) are present in all three areas mentioned: IC design, elderly care, and the oil and gas industry. WSN can be utilized in IC design for monitoring and controlling various components. In elderly care, WSN can be used for remote monitoring of patients' health and safety. In the oil and gas industry, WSN can be employed for monitoring pipelines, equipment, and environmental conditions. Therefore, all of these areas offer potential opportunities for the application of WSN technology.
8.
Jamming is the attack of
Correct Answer
C. pHysical layer.
Explanation
The correct answer is Physical layer. Jamming is an attack that targets the physical layer of a network. It involves disrupting or interfering with the transmission of signals, making it difficult or impossible for legitimate communication to occur. This type of attack can be carried out through various means, such as using high-power signals or electromagnetic interference, with the intention of causing disruption or denial of service. By targeting the physical layer, the attacker aims to disrupt the transmission of data and compromise the overall network performance.
9.
Probing and Redundancy are defenses at
Correct Answer
B. Network layer.
Explanation
Probing and Redundancy are defenses at the network layer. The network layer is responsible for routing and forwarding data packets across different networks. Probing is a defense mechanism that involves sending test packets to check the availability and responsiveness of network devices. Redundancy, on the other hand, is a technique used to ensure network reliability by duplicating network components or paths. These defenses are specifically implemented at the network layer to enhance the overall security and efficiency of network communication.
10.
Flooding attack at transport layer is defended by
Correct Answer
A. Limiting number of connections.
Explanation
A flooding attack at the transport layer can be defended by limiting the number of connections. This means that a system can restrict the number of connections that a client can establish with the server. By doing so, the system can prevent an attacker from overwhelming the server with a large number of connection requests, effectively mitigating the impact of the flooding attack. This defense mechanism helps to ensure that the server's resources are not exhausted and can continue to function properly.
11.
Some security threat in WSNs are
Correct Answer
D. All above.
Explanation
The correct answer is "All above." This means that all of the mentioned security threats in WSNs, including insertion of malicious code, interception of messages, and injection of false data, are potential threats that need to be addressed. These threats can compromise the integrity, confidentiality, and reliability of the wireless sensor network, making it crucial to implement appropriate security measures to mitigate these risks.
12.
Routing security in wireless sensor networks faces the problem that
Correct Answer
A. Current routing protocols for wireless sensor networks do not consider security.
Explanation
The correct answer is that current routing protocols for wireless sensor networks do not consider security. This means that the existing protocols do not have built-in mechanisms or features to ensure the security of the routing process. This can lead to vulnerabilities and potential attacks on the network, compromising its integrity and confidentiality. To address this issue, new routing protocols need to be developed that prioritize security and implement measures such as authentication, encryption, and intrusion detection to protect the network from malicious activities.
13.
Some routing related attacks are
Correct Answer
D. Both a and b.
Explanation
The correct answer is "Both a and b." This means that both selective forwarding and sinkhole attacks are routing related attacks. Selective forwarding refers to the act of selectively dropping or forwarding packets in a network, while a sinkhole attack involves diverting network traffic to a specific target or node. The option "Both a and b" implies that both of these attacks fall under the category of routing related attacks.
14.
Grid’s Location Service (GLS) uses
Correct Answer
B. Distributed location servers
Explanation
GLS uses distributed location servers. This means that the location information is not stored in a single centralized server but is distributed across multiple servers. This approach offers several advantages such as improved scalability, fault tolerance, and reduced network congestion. By distributing the location servers, GLS can handle a larger number of requests and provide more reliable and efficient location services to its users.
15.
Hello Flooding attack at transport layer (in WSN) is defended by
Correct Answer
D. All above.
Explanation
The correct answer is "All above" because all of the mentioned defenses can help in defending against a flooding attack at the transport layer in a Wireless Sensor Network (WSN). Limiting the number of connections can prevent an attacker from overwhelming the network with excessive traffic. Stopping or deactivating the sensors can halt the transmission of malicious messages. Authenticating all messages can ensure that only legitimate messages are processed, preventing the network from being flooded with fake or harmful messages. Therefore, all of these defenses together can provide a comprehensive protection against flooding attacks.
16.
A Sybil node in WSN is defined as
Correct Answer
C. A malicious or subverted node forges the identities of more than one node or fabricates identity
Explanation
The correct answer is a malicious or subverted node forges the identities of more than one node or fabricates identity. This definition accurately describes what a Sybil node is in a Wireless Sensor Network (WSN). Sybil nodes are nodes that pretend to be multiple nodes by forging their identities. This can be done to gain control over the network, manipulate data, or launch attacks. By fabricating identities, Sybil nodes can deceive other nodes and disrupt the normal functioning of the network.
17.
A sensor is mainly composed of microcontroller, battery and _____________?
Correct Answer
B. Antenna
Explanation
A sensor is mainly composed of a microcontroller, battery, and an antenna. The antenna is an essential component of a sensor as it is responsible for receiving and transmitting signals. It allows the sensor to detect and capture data from its surroundings and communicate that information to the microcontroller. The microcontroller then processes the data and performs the necessary actions based on the sensor's programming. The battery provides power to the sensor, enabling it to function properly. Therefore, an antenna is a crucial component of a sensor system.
18.
Routing security in wireless sensor networks faces the problem that
Correct Answer
A. Current routing protocols for wireless sensor networks do not consider security.
Explanation
The correct answer is that current routing protocols for wireless sensor networks do not consider security. This means that the existing protocols used for routing in wireless sensor networks do not have built-in mechanisms or features to address security concerns. This can pose a significant problem as it leaves the network vulnerable to various security threats and attacks. Without considering security in routing protocols, the network becomes more susceptible to unauthorized access, data tampering, and other malicious activities. Therefore, it is crucial to develop and implement routing protocols that prioritize security in wireless sensor networks.
19.
A sensor is mainly composed of microcontroller, antenna and _____________?
Correct Answer
B. Battery
Explanation
A sensor is mainly composed of a microcontroller, antenna, and a battery. The battery provides the necessary power for the sensor to function and transmit data. Without a battery, the sensor would not be able to operate and collect information.
20.
GPS devices can work during daylight and night hours.
Correct Answer
D. Both b and c.
Explanation
Both options b and c are correct because GPS devices can work during both daylight and night hours, regardless of the time of day. Additionally, GPS devices can function in various environments and conditions, including situations where nodes are mobile or when they need to self-configure. The combination of options b and c covers the different aspects of GPS device functionality.
21.
WSN opportunities are in?
Correct Answer
D. All above.
Explanation
The correct answer is "All above" because WSN (Wireless Sensor Network) opportunities can be found in IC design, elderly care, and the oil and gas industry. WSN technology can be applied in IC design for various purposes such as monitoring and control. In elderly care, WSN can be used to monitor the health and safety of elderly individuals. In the oil and gas industry, WSN can be utilized for remote monitoring and control of equipment and processes. Therefore, all the given options are valid opportunities for WSN.
22.
A sinkhole node in WSN is defined as
Correct Answer
B. A node that attract nearly all the traffic from a particular area through a compromised node
Explanation
A sinkhole node in WSN is a node that attracts nearly all the traffic from a particular area through a compromised node. This means that the sinkhole node manipulates the network in such a way that it diverts most of the traffic towards itself, potentially causing a denial of service or intercepting sensitive information. The compromised node acts as a gateway for the traffic, allowing the sinkhole node to gain control over the network. This can be a serious security threat in wireless sensor networks.