Tag: science & technology

The OSI (Open Systems Interconnection) model has exactly 7 layers: Physical (1), Data Link (2), Network (3), Transport (4), Session (5), Presentation (6), and Application (7). This is a fundamental networking concept that all network professionals memorize. The layers form a stack from hardware (Physical) to user-facing software (Application).

Java 1.5 (also known as Java 5) was codenamed 'Tiger' during development. Sun Microsystems used animal codenames for major Java releases: 1.3 was 'Kestrel', 1.4 was 'Merlin', 1.5 was 'Tiger', and 1.6 was 'Mustang'. This naming convention helps developers and administrators refer to specific versions during discussion and planning.

Digital signatures involve a variable number of parties depending on the signature hierarchy and PKI structure. Basic scenarios involve 2 parties (sender signing, receiver verifying), but with certificate authorities, registration authorities, and timestamp authorities, there can be 3, 4, or more parties. Some implementations use just sender and receiver (2 parties), while enterprise PKI systems involve certificate authorities, registration authorities, policy servers, and timestamp services. Therefore, the number depends on the specific signature hierarchy deployed.

You can track email forwarding through various technical means. Email headers contain 'Received' fields showing forwarding hops, and forwarding services often add 'X-Forwarded-For' or similar headers. Additionally, tracking pixels, read receipts, and forwarded message notifications in email clients can reveal forwarding activity. The question format is unusual with option D being informal, but the statement is technically accurate - email forwarding leaves traceable artifacts.

White Hat hackers are ethical hackers who use their skills to improve security by finding vulnerabilities and helping organizations fix them. They operate with permission and often work as security consultants. This contrasts with Black Hats (malicious hackers), Grey Hats (somewhere between), and government hackers. The term comes from Western movies where 'good guys' wore white hats. White Hats follow responsible disclosure practices.

This is an exact duplicate of question 15181. Nmap (Network Mapper) is the correct tool for port scanning. It's designed specifically to discover open ports and services on network targets. Given an IP address, nmap scans the target and enumerates open ports with service detection. Wireshark (formerly Ethereal) is for packet capture and analysis, not port scanning. 'Switch sniffer' is not a recognized security tool.

A honeypot is a decoy system designed to attract potential attackers, detect their attempts, and study their behavior. It appears as a legitimate target but actually traps cyber criminals by diverting them from real systems. It's not used for hacking, storing data, or downloading content.

The OSI (Open Systems Interconnection) model has exactly 7 layers: Physical, Data Link, Network, Transport, Session, Presentation, and Application. This seven-layer architecture is a fundamental conceptual framework used to understand network communications.

A DDoS (Distributed Denial of Service) attack floods a website with massive traffic from multiple sources, overwhelming its resources and taking it offline. The term 'DDOS' is the correct answer, though 'unlimited pings' describes a similar concept in simpler terms.

HTTPS uses port 443 by default for secure, encrypted web communication. Port 80 is for standard HTTP, port 21 is for FTP, and port 139 is for NetBIOS session service. The 's' in HTTPS indicates a secure connection on port 443.