Data & Network Security MCQ Quiz - Objective Question with Answer for Data & Network Security - Download Free PDF

The Correct answer is A, B, C and E only

Key Points

• The Indian Computer Emergency Response Team (CERT-In), established in 2004 under the Ministry of Electronics and Information Technology, is the national agency responsible for managing cybersecurity incidents in India.
• Formed under Section 70B of the Information Technology Act, 2000, CERT-In focuses on securing India’s cyberspace by:
  • Collection, analysis, and dissemination of information on cyber incidents.
  • Forecast and alerts of cyber security incidents
  • Emergency measures for handling cyber security incidents
  • Coordination of cyber incident response activities.
  • Issue guidelines, advisories, vulnerability notes, and whitepapers relating to information security practices, procedures, prevention, response and reporting of cyber incidents.
  • Such other functions relating to cyber security as may be prescribed.
• Vision:
  • To proactively secure India’s cyberspace.
• Mission:
  • To strengthen the security of India’s communication and information infrastructure through proactive measures and collaboration.
• Objectives:
  • Prevent cyber attacks on India’s cyberspace
  • Respond to cyber attacks, minimizing damage and recovery time
  • Reduce national vulnerability to cyber threats

Explanation:

In the context of modern anti-virus software, one of the most significant advancements aiding real-time threat detection is the integration of cloud-based detection mechanisms. This feature has become increasingly prevalent due to its efficiency and effectiveness in identifying and mitigating security threats as they emerge.

Cloud-Based Detection:

Definition: Cloud-based detection is a feature in modern anti-virus software that leverages cloud computing technology to analyze potential threats. Unlike traditional anti-virus solutions that rely solely on local databases and signatures, cloud-based detection utilizes remote servers to process and examine suspicious files and activities in real-time.

Working Principle: When a file or activity is flagged as suspicious by the anti-virus software, it is uploaded to the cloud for further analysis. The cloud-based system, which is often equipped with advanced machine learning algorithms and vast threat intelligence databases, quickly evaluates the potential threat. The results are then relayed back to the local software, which takes appropriate actions, such as quarantining the file or alerting the user.

Advantages:

• Real-Time Updates: Cloud-based detection allows for real-time updates of threat databases, ensuring that the anti-virus software can protect against the latest threats as soon as they are discovered.
• Advanced Analytics: The cloud environment can leverage powerful analytical tools and machine learning algorithms to detect sophisticated and emerging threats that might evade traditional signature-based detection.
• Reduced Local Resource Consumption: By offloading complex analysis to the cloud, the local system's resources are conserved, leading to better performance and less system slowdown.
• Scalability: Cloud-based detection systems can scale up to handle large volumes of data, providing robust protection even against large-scale attacks.
• Collaborative Defense: Threat intelligence gathered from multiple users and systems can be aggregated in the cloud, creating a more comprehensive and up-to-date defense mechanism.

Disadvantages:

• Dependence on Internet Connectivity: Cloud-based detection requires a reliable internet connection to communicate with remote servers, which can be a limitation in environments with poor connectivity.
• Privacy Concerns: Uploading files and data to the cloud for analysis raises concerns about data privacy and security, especially if sensitive information is involved.
• Latency: Although cloud-based systems are designed to be fast, there can be some latency involved in uploading and analyzing files remotely, which might delay the response to threats.

Applications: Cloud-based detection is widely used in modern anti-virus software designed for both individual and enterprise-level security. It is particularly beneficial in environments where up-to-date threat intelligence and real-time protection are critical.

Correct Option Analysis:

The correct option is:

Option 2: Cloud-based detection

This option correctly identifies a key feature of modern anti-virus software that enhances real-time threat detection. Cloud-based detection leverages the power of cloud computing to provide up-to-date protection against the latest threats, utilizing advanced analytics and collaborative intelligence.

Additional Information

To further understand the analysis, let’s evaluate the other options:

Option 1: Manual updates

Manual updates require users to download and install the latest virus definitions and software updates manually. While this method ensures that the software is up-to-date with the latest threat information, it does not provide real-time threat detection. The effectiveness of manual updates depends on the frequency with which users perform these updates, which can lead to vulnerabilities if updates are delayed.

Option 3: Offline scanning

Offline scanning refers to the ability of anti-virus software to scan the system for threats without an active internet connection. This method is useful for detecting known threats based on the virus definitions already present in the local database. However, offline scanning does not provide real-time threat detection and cannot protect against new or emerging threats that require up-to-date information from the cloud or internet.

Option 4: Passive scanning

Passive scanning involves monitoring the system for suspicious activity without actively scanning files or system processes in real-time. This method is less resource-intensive and can be useful in certain scenarios, but it does not offer the same level of protection as active or real-time scanning. Passive scanning may fail to detect threats immediately, allowing malware to execute before any intervention occurs.

Conclusion:

In conclusion, cloud-based detection stands out as the most effective feature for real-time threat detection in modern anti-virus software. By leveraging the power of cloud computing, it provides up-to-date protection against the latest threats, advanced analytics, and collaborative intelligence. While other options like manual updates, offline scanning, and passive scanning have their own merits, they do not offer the same level of real-time protection as cloud-based detection. Understanding these differences is crucial for selecting the right anti-virus solution to ensure comprehensive and timely protection against security threats.

The correct answer is (1), (2), (3), (4).

Key Points

• Phases of a Computer Virus Infection Cycle:
  • Dormant Phase: Initially, the virus remains inactive without self-replicating or harming the system.
    • It silently resides within the infected computer, awaiting activation.
  • Propagation Phase:
    • The virus begins self-replicating by creating copies of its malicious code and storing them in different parts of the system.
    • Some viruses morph during replication, altering their code to evade detection.
  • Trigger Phase:
    • At this stage, the virus becomes active based on predefined conditions such as a set number of replications or a specific time frame.
    • Once triggered, it prepares to execute its malicious intent.
  • Execution Phase:
    • The virus releases its payload, which can range from data deletion to displaying intrusive ads, causing disruptions or damage to the infected system.

The Correct answer is B, C and D only.

Key Points

• Antivirus protection is a crucial measure that helps in detecting, preventing, and removing malware, ensuring the integrity and security of data.
• Data encryption is a method of converting data into a code to prevent unauthorized access, thereby protecting sensitive information during storage and transmission.
• A firewall acts as a barrier between a trusted network and an untrusted network, monitoring and controlling incoming and outgoing network traffic based on predetermined security rules.

 Additional Information

• Book marking
  • Book marking is a method of saving a web address for future reference. It does not contribute to data security measures.
• Data diddling
  • Data diddling refers to the unauthorized altering of data before or during entry into a computer system. It is a form of security breach rather than a security measure.

The Correct answer is Assertion (A) is true, but Reason (R) is false.

Key Points

• Viruses are indeed responsible for data theft. They can infect systems, steal sensitive information, and transmit this data to malicious actors.
• Data theft can occur through various types of malware, including keyloggers, spyware, and trojans, which are often classified under the broader category of viruses.
• While antiviruses play a crucial role in detecting and removing viruses, they are not foolproof. Advanced persistent threats (APTs) and zero-day vulnerabilities can sometimes bypass antivirus protection.
• Antiviruses can mitigate the risk of data theft by detecting and removing known malware, but they cannot guarantee complete security, especially against new and sophisticated threats.
• Effective data protection requires a comprehensive security strategy, including regular software updates, strong passwords, encryption, and user education, in addition to antivirus software.

The correct answer is Hackers

Key Points

• A hacker is someone skilled in breaching cybersecurity defenses, and they are often categorized using a 'hat' system in the cybersecurity world.
• In the realm of cyberspace, there are three primary classifications of individuals:
  • White Hats
  • Grey Hats
  • Black Hats
• ​White Hat:
  • ​White hat hackers are individuals or cybersecurity professionals who use their skills and knowledge for ethical and legitimate purposes.
  • They often work to protect computer systems, networks, and software from security vulnerabilities and threats.
• Black Hat:
  • ​Black hat hackers are individuals or groups who engage in hacking and cyber-attacks with malicious intent.
  • They often break into computer systems, steal sensitive information, distribute malware, and cause harm to individuals, organizations, or even nations for personal gain, financial profit, or other malicious purposes. Black hat hacking is illegal and unethical.
• Grey Hat:
  • Grey hat hackers occupy a middle ground between white hats and black hats.
  • Unlike white hats, they typically don't seek permission to hack systems. However, unlike black hats, they refrain from engaging in other illegal activities.

Additional Information

• Attackers:
  • "Attackers" refers to individuals or entities that carry out malicious actions or activities with the intent to harm, exploit, or compromise computer systems, networks, or data.
• Spammers:
  • ​"Spammers" are individuals or entities that engage in the practice of sending unsolicited and often irrelevant or inappropriate messages or content, typically through electronic means such as email, social media, or instant messaging. 
• Phisher:
  • A "phisher" is an individual or entity that engages in phishing, which is a form of cyber-attack where the attacker attempts to deceive people into divulging sensitive or confidential information, such as login credentials, financial information, or personal details. ​

The correct answer is Masquerading.

Key Points

• Spoofing or Masquerading is a deceptive tactic used by individuals or programs to impersonate someone or something else by altering data, with the intent to gain an unfair or unauthorized advantage.
• In simpler terms, it involves cybercriminals pretending to be someone else, such as a different person, company, or entity, to carry out malicious actions.
• Spoofing can be executed through various communication channels and may vary in technical complexity.
• These attacks often incorporate social engineering, wherein scammers exploit human vulnerabilities, like fear, greed, or limited technical expertise, to manipulate their victims.
• Masquerading, also known as spoofing, can take several forms, including:
  • Email Spoofing
  • IP Spoofing
  • Caller ID Spoofing
  • Website Spoofing
  • ARP Spoofing Etc

Additional Information

• Sniffing:
  • ​Sniffing attack involves the unauthorized interception and theft of data by capturing network traffic using a packet sniffer, which is a software or tool designed for capturing network packets.
  • When data is transmitted across networks without encryption, the contents of these network packets can be easily read and accessed using a sniffer.
• Phishing:
  • The practice of sending fake emails in the name of reputed companies to retrieve personal information such as passwords and credit card numbers.
  • Phishing is a fraudulent attempt to obtain sensitive information or data, such as usernames, passwords, and credit card details.
  • It is the act of disguising oneself as a trustworthy entity in electronic communication.
• Spooling:
  • In computing, spooling is a specific technique within the realm of multi-programming designed for the efficient transfer of data between various devices.
  • In modern computer systems, it is commonly employed to facilitate communication between a computer application and a slower peripheral device, such as a printer.

The Correct answer is (i), (ii) (iii) and (iv) are correct

Key Points

• A network protocol is a defined set of rules governing the transmission of data among various devices within a shared network.
• It facilitates communication between connected devices, overcoming differences in their internal processes, structure, or design.
• Network protocols are essential for enabling seamless communication globally, playing a crucial role in contemporary digital communications.
• UDP (User Datagram Protocol):
  • UDP is a transport layer protocol that operates in the Internet Protocol (IP) suite.
  • It provides a connectionless and lightweight communication method.
  • UDP is often used for applications that prioritize speed and efficiency over guaranteed delivery, such as real-time streaming, online gaming, and DNS.
• SMTP (Simple Mail Transfer Protocol):
  • ​SMTP is a communication protocol used for the transmission of email messages between servers.
  • It is part of the application layer protocols in the TCP/IP stack.
  • SMTP is responsible for sending emails from a client to a server or between servers.
  • It is a fundamental protocol for email communication.
• TCP (Transmission Control Protocol):
  • TCP is a core transport layer protocol in the Internet Protocol suite.
  • It provides reliable, connection-oriented communication between devices on a network.
  • TCP ensures that data is delivered in the correct order and without errors.
  • It is widely used for applications that require reliable data transfer, such as web browsing, file transfer (FTP), and email (with protocols like POP and IMAP).
• Telnet:
  • Telnet, developed in 1969, is a protocol offering a command line interface for communicating with a remote device or server, commonly used for remote management and initial device setup, particularly for network hardware.
  • Telnet stands for Teletype Network and can also be used as a verb, meaning 'to telnet' is to establish a connection using the Telnet protocol.
  • Telnet facilitates bidirectional interactive text-oriented communication through a virtual terminal connection over 8 bytes. 

Additional Information

• Various network protocols have been established and published by different organizations, including:
  • The Institute of Electrical and Electronics Engineers (IEEE)
  • The Internet Engineering Task Force (IETF)
  • The International Organization for Standardization (ISO)
  • The International Telecommunications Union (ITU)
  • The World Wide Web Consortium (W3C)

The Correct answer is Topology.

Key Points

• Network Topology:
  • ​Network Topology refers to the physical or logical layout of interconnected devices in a computer network.
  • It defines how different network devices are arranged and how they communicate with each other.
  • Topology plays a crucial role in determining the efficiency, reliability, and scalability of a network.
  • There are several types of network topologies, each with its own advantages and disadvantages:
• Bus Topology:
  • ​Single central cable (bus) to which all network devices are connected.
  • Simple and cost-effective but can face performance issues as the network grows.
• Star Topology:
  • ​All devices are connected to a central hub or switch.
  • Easy to install and manage, and failure of one device doesn't affect others.
• Ring Topology:
  • ​Devices are connected in a circular or ring-like fashion.
  • Data travels in one direction, and it's relatively easy to install.
• Mesh Topology:
  • ​Devices are interconnected, and each device may have a connection to every other device.
  • Provides high redundancy and reliability but can be costly and complex.
• Tree Topology:
  • ​Combination of star and bus topologies.
  • Suitable for larger networks, providing scalability.
• Hybrid Topology:
  • ​Combination of two or more different types of topologies.
  • Offers flexibility and scalability.

Additional InformationKey Concepts:

• Nodes: Devices or computers connected in the network.
• Links: Communication paths between nodes.
• Hub/Switch: Central devices managing connections in star or mesh topologies.
• Data Transmission: The way data travels through the network (unidirectional or bidirectional).

Routing:

• Routing is the process of directing data from its source to its destination across multiple interconnected networks.
• Explanation: Routers play a key role in routing by determining the most efficient path for data packets to reach their intended destinations.
• Examples: Internet routers use routing protocols to guide data across the global network.

Bandwidth:

• Bandwidth refers to the data transfer capacity of a network, representing the maximum rate of data transmission.
• Explanation: It is typically measured in bits per second (bps) and determines how much data can be transmitted over the network in a given timeframe.
• Examples: A network with higher bandwidth can handle more simultaneous data transmissions without slowing down.

Switching:

• Switching involves the process of forwarding data from its source to its destination within the same network.
• Explanation: Network switches play a vital role in connecting devices within a local area network (LAN) and facilitate communication by forwarding data only to the device that needs it.
• Examples: Ethernet switches are commonly used in LANs to enable efficient data transfer between connected devices.

The correct answer is Malware:

Key Points

• It is a broad term that refers to a variety of malicious programs that are used to damage computer systems, gather sensitive information, or gain access to private computer systems. 
• Threats to Computer Security Malware stands for malicious software. 
• It includes computer viruses, worms, trojan horses, rootkits, spyware, adware, etc.
• Examples of Malware are:
  • Computer viruses.
  • Worms.
  • Trojan horses.
  • Ransomware.
  • Spyware
  • Adware.
  • Scareware.

Additional Information

• Botnet:
  •  A botnet is a collection of internet-connected devices infected by malware that allow hackers to control them.
  • Cybercriminals use botnets to instigate botnet attacks, which include malicious activities such as credentials leaks, unauthorized access, data theft, and DDoS attacks.
  • The word "botnet" is a portmanteau of the words "robot" and "network". 
• ​Censorship:
  • ​Censorship is the suppression of speech, public communication, or other information.
  • The National Coalition Against Censorship (NCAC), was founded in 1974.
  • American Library Association (ALA)  set up the Office of Intellectual Freedom (OIF) in 1967.
  • Censorship can be applied to the following: books and other print, materials, speech, photographs, films, TV, radio programs, digital materials, and the Internet.
• Cyberwarfare:
  • ​Cyberwarfare is the use of cyber attacks against an enemy state, causing comparable harm to actual warfare and/or disrupting vital computer systems.
  • Some intended outcomes could be espionage, sabotage, propaganda, manipulation or economic warfare.

The correct answer is B, D, A, C.

Key Points

• Creeper Virus
  • Creeper, the first virus recorded was an experimental computer program developed by Bob Thomas at BBN in 1971. 
  • Initially, it was designed to move between DEC PDP-10 mainframe computers connected through the ARPANET and running the TENEX operating system. Later, Ray Tomlinson modified it to not only move but also copy itself between computers. 
  • Its only notable effect was displaying the message "I'M THE CREEPER: CATCH ME IF YOU CAN" on the teletype.
•  Animal (Trojan):
  • ​The first trojan encountered in the wild was ANIMAL, which was released in 1975.
  • Since then, countless trojan variants have emerged, falling into various categories.
  • Trojans are deceptive programs that appear to serve one purpose but actually perform a different, malicious function.
  • They often masquerade as free software, videos, music, or seemingly legitimate advertisements.
• Morris Worm:
  • ​The Morris worm, also known as the Internet worm, made headlines on November 2, 1988, as one of the earliest computer worms to spread through the Internet.
  • It was unleashed at 8:30 p.m. on November 2, 1988, from the Massachusetts Institute of Technology network.
  • The Morris worm took advantage of weak passwords in its exploits. Over time, Morris's methods became less effective as security measures improved. 
• Storm Botnet:
  • ​The Storm botnet, also known as the Storm worm botnet, was a network of compromised computers, often referred to as "zombies."
  • It was created and controlled remotely by the Storm Worm, a Trojan horse that spread through email spam.
  • This botnet was first observed on the Internet in January 2007 and gained its name from the storm-related subject lines used in its initial spam emails, such as "230 dead as storm batters Europe." 

The Correct answer is A - II, B - IV, C - III, D - I.

Key Points

• Packet filtering firewall:
  • A packet filtering firewall is a network security measure regulating incoming and outgoing data flow.
  • ]It scrutinizes each packet, consisting of user data and control information, based on predefined rules.
  • If a packet successfully passes the examination, the firewall permits it to proceed to its destination; otherwise, it rejects the packet.
  • A packet filtering firewall evaluates individual packets of data based on a predefined set of rules.
  • These rules determine whether the packet is allowed to pass through or if it should be blocked.
  • This type of firewall operates at the network layer (Layer 3) of the OSI model, inspecting IP packets and making decisions based on criteria such as source and destination IP addresses, port numbers, and protocols.
• Stateful packet inspection firewall:
  • ​A stateful firewall is a type of firewall positioned at Layers 3 and 4 of the OSI model.
  • It actively monitors and tracks the state of ongoing network connections while scrutinizing incoming traffic for potential risks.
  • Key functionalities include blocking potentially harmful traffic from entering or leaving a network.
  • Monitoring the state and context of network communications is crucial for identifying threats, considering factors like the source, destination, and content of data packets. 
  • Stateful packet inspection (SPI) firewall, also known as dynamic packet filtering, goes beyond the basic packet filtering by keeping track of the state of active connections.
  • It maintains a state table or directory of outbound TCP connections. 
• ​Application level Gateway:
  • An application-level gateway (ALG) is a security component enhancing a computer network's firewall or NAT.
  • It allows for the integration of customized NAT traversal filters to support address and port translation for specific application layer protocols like FTP, BitTorrent, SIP, RTSP, and file transfer in instant messaging applications.
  • An Application Level Gateway (ALG), also referred to as an application proxy, operates at the application layer (Layer 7) of the OSI model. 
• Circuit level Gateway:​
  • ​A circuit-level gateway firewall enhances security between UDP and TCP connections, serving as a handshake mechanism between trusted clients or servers and untrusted hosts.
  • Typically operating at the session layer of the OSI model, these gateways confirm session requests through packet handshaking, determining the validity of the connection.
  • A Circuit Level Gateway operates at the session layer (Layer 5) of the OSI model.
  • It establishes a circuit or pathway for communication between two parties, typically without inspecting the actual content of the data
  • It is often used in situations where there is a high level of trust, such as internal networks, as it does not perform extensive packet inspection or filtering.

The correct answer is Both Statement I and Statement II are correct

Explanation:

• Statement I: Bacteria are programs that generally cause denial-of-service attacks.
  • ​Bacteria are programs that generally cause denial-of-service attacks.
  • They do not affect the existing files or programs. Since they are independent stand-alone programs, they replicate themselves and start growing exponentially, viz. one copy to two, two to
    four, four to eight, and so on.
• Statement II: Denial of service attacks do not affect the existing files or programs:
  • ​A Denial-of-Service (DoS) attack is a deliberate attempt to render a machine or network unavailable to its intended users. This is achieved by overwhelming the target with excessive traffic or sending it data that causes it to crash. 
  • Though DoS attacks usually do not lead to theft or significantly affect the existing files or programs. or assets,but they can impose substantial time and financial burdens on the victim for mitigation and recovery.

The Correct answer is Bob Thomas.

Key Points

• Creeper, the first virus recorded was an experimental computer program developed by Bob Thomas at BBN in 1971. 
• Initially, it was designed to move between DEC PDP-10 mainframe computers connected through the ARPANET and running the TENEX operating system. Later, Ray Tomlinson modified it to not only move but also copy itself between computers. 
• Its only notable effect was displaying the message "I'M THE CREEPER: CATCH ME IF YOU CAN" on the teletype.

Additional Information

• Reaper, developed by Ray Tomlinson in 1972, was the first antivirus software designed to remove Creeper, the earliest computer worm, from the ARPANET.
• Whitfield Diffie is renowned for his groundbreaking work on the Diffie-Hellman key exchange.
  • He played a pivotal role in the development of public-key cryptography alongside Martin Hellman and Ralph Merkle.
• Martin Hellman
  • He played a significant role in the Beyond War movement and was the principal editor of the "BEYOND WAR: A New Way of Thinking" booklet.
  • Additionally, from 1994 to 1996, he served on the National Research Council's Committee to Study National Cryptographic Policy, which contributed to implemented recommendations. 
  • Hellman was elected as a member of the National Academy of Engineering in 2002.
• Frederick B. Cohen
  • ​He is an American computer scientist renowned for inventing techniques to defend against computer viruses.
  • He is credited with providing the definition of a "computer virus."
  • Cohen is celebrated for his groundbreaking contributions in computer virology, the creation of high-integrity operating system mechanisms that are now widely employed, and the automation of protection management functions.

The Correct answer is A, B, C and E only

Key Points

• The Indian Computer Emergency Response Team (CERT-In), established in 2004 under the Ministry of Electronics and Information Technology, is the national agency responsible for managing cybersecurity incidents in India.
• Formed under Section 70B of the Information Technology Act, 2000, CERT-In focuses on securing India’s cyberspace by:
  • Collection, analysis, and dissemination of information on cyber incidents.
  • Forecast and alerts of cyber security incidents
  • Emergency measures for handling cyber security incidents
  • Coordination of cyber incident response activities.
  • Issue guidelines, advisories, vulnerability notes, and whitepapers relating to information security practices, procedures, prevention, response and reporting of cyber incidents.
  • Such other functions relating to cyber security as may be prescribed.
• Vision:
  • To proactively secure India’s cyberspace.
• Mission:
  • To strengthen the security of India’s communication and information infrastructure through proactive measures and collaboration.
• Objectives:
  • Prevent cyber attacks on India’s cyberspace
  • Respond to cyber attacks, minimizing damage and recovery time
  • Reduce national vulnerability to cyber threats