Computer Science - IT MCQs
Topic Notes: Computer Science - IT
<p>MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.</p>
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
211
What is the primary role of a 'firewall' in network security, including email communication?
Answer:
To filter network traffic and block unauthorized access.
A firewall acts as a barrier between a trusted internal network and untrusted external networks (like the internet), controlling incoming and outgoing network traffic based on security rules.
212
Why is it generally NOT recommended to send highly sensitive personal information via unencrypted email?
Answer:
Unencrypted emails can be intercepted and read by unauthorized parties.
Unencrypted emails travel across networks in plaintext, making them vulnerable to interception and eavesdropping by malicious actors. Encryption is essential for protecting sensitive data.
213
HDSL uses which encoding method?
Answer:
2B1Q
HDSL uses 2 Binary, 1 Quaternary (2B1Q) line coding to transmit data efficiently.
214
Which protocol is associated with sending secure emails over an encrypted connection using SMTP?
Answer:
SMTPS
SMTPS (Simple Mail Transfer Protocol Secure) is the version of SMTP that uses SSL/TLS encryption for secure email transmission. POP3S and IMAPS are for secure retrieval, and HTTPS is for secure web browsing.
215
The most widely used technology in time-division switching is known as what?
Answer:
TSI
Time-Slot Interchange (TSI) is a fundamental technique in time-division switching where data from one time slot is moved to another.
216
Which type of email attachment poses the highest security risk if mishandled?
Answer:
Executable (.exe, .bat) files.
Executable files (.exe, .bat, .zip containing executables) pose the highest risk because they can contain and run malicious code directly on your system once opened, unlike text, image, or even PDF files which require exploits to be dangerous.
217
What is the main advantage of using IMAP over POP3 for email retrieval?
Answer:
IMAP keeps emails on the server, allowing access from multiple devices.
IMAP allows users to access their emails from multiple devices because a copy of the email remains on the server. POP3 typically downloads emails to a single device and deletes them from the server.
218
Which of the following is commonly used for secure communication over the internet, including email services?
Answer:
SSL/TLS
SSL (Secure Sockets Layer) and its successor TLS (Transport Layer Security) are cryptographic protocols designed to provide communication security over a computer network, widely used for secure email (e.g., SMTPS, IMAPS, POP3S).
219
Which email status indicates that an email tried to be delivered but was temporarily rejected by the recipient's server?
Answer:
Soft Bounce
A soft bounce indicates a temporary delivery issue, such as a full inbox, server downtime, or a message that's too large. The sending server will typically retry delivery later. A hard bounce is a permanent failure.
220
Why is it advisable to avoid including highly sensitive information (e.g., credit card numbers, social security numbers) directly in the body of an email?
Answer:
Emails are not inherently secure and can be intercepted or stored insecurely.
Email, by default, is not a secure communication channel. Sensitive data sent in plaintext can be intercepted, read, and misused by unauthorized parties. More secure methods like encrypted platforms or secure file transfer should be used.