Computer Science Test 4 Nddc Scholarship

Confidentiality of data is a core principle of information security. It ensures that sensitive information is accessible only to those authorized to have it. This is typically achieved through access controls, such as passwords and file permissions, as well as encryption, which prevents unauthorized parties from making sense of the data even if they manage to intercept it.

Polymorphic viruses are a sophisticated type of malware that uses a mutation engine to change its own appearance or signature each time it replicates. Because traditional antivirus programs look for specific, static 'signatures' to identify threats, these viruses are difficult to detect since their 'fingerprint' is constantly evolving while their underlying malicious function remains the same.

The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense. It is historically significant in computer security as it was responsible for the development of ARPANET, the precursor to the modern internet. DARPA continues to fund cutting-edge research in cybersecurity, networking, and artificial intelligence.

Computer security typically relies on three main approaches: Prevention (blocking unauthorized access), Detection (identifying when a breach occurs), and Response (taking action to mitigate damage after an attack). Together, these form a comprehensive defense strategy that acknowledges that while prevention is ideal, detection and response are necessary when barriers are breached.

A firewall serves as the primary perimeter defense for a network. It acts as a gatekeeper that inspects all incoming and outgoing traffic based on a defined set of security rules. Just as a security guard checks IDs, the firewall checks the source and destination of data packets to ensure they are legitimate before allowing them to pass between the private network and the internet.

A packet sniffer is a tool that captures data packets as they travel across a network. For it to intercept these packets, the device running the sniffer must be physically or logically connected to the same network segment where the traffic is flowing. This allows the sniffer to 'listen' to the digital conversation happening between other devices on that specific local network.

Active scripting (such as JavaScript) allows web pages to be dynamic and interactive. However, in high-risk or restricted zones, it is safer to disable it because hackers can use scripts to automatically execute malicious code or steal session cookies. Disabling active scripting ensures that a browser only displays static content, significantly reducing the 'attack surface' of the web browser.

Phishing scams typically impersonate trusted digital services (PayPal, eBay) or official government and financial institutions (FBI, IRS, Banks) to create a sense of urgency. These are 'social engineering' attacks. A 'paper scam' is not a recognized category of digital phishing, as phishing specifically refers to fraudulent communications sent via electronic methods like email.

Ciphering is the process of encryption, which transforms readable plaintext into scrambled ciphertext. The resulting text is intentionally rendered unreadable and nonsensical to anyone who does not possess the correct cryptographic key. Only by applying the proper decryption key can the data be returned to its original, understandable form.

Digital Rights Management (DRM) refers to the various technological tools and protocols used by hardware manufacturers and copyright holders to control the use of digital content after sale. This includes limiting the number of devices a movie can be played on or preventing the unauthorized copying of software, often utilizing encryption and digital watermarking to enforce these restrictions.