Communication and Network Security

Correct Answer: Firewall

A firewall is the primary security mechanism used to detect and prevent unauthorized network traffic from entering or leaving an organization's network. It acts as a barrier between trusted internal networks and untrusted external networks, such as the internet. Firewalls use a set of predefined rules to allow or block specific types of network traffic based on various criteria, including source and destination IP addresses, port numbers, and protocols. Modern firewalls often include packet inspection capabilities, which enable them to examine the contents of network packets and make decisions based on the application layer data. This allows firewalls to provide more advanced protection against sophisticated threats and unauthorized access attempts.

Correct Answer: Two-factor authentication provides an extra layer of security by requiring a second factor in addition to the password to access an account.

Two-factor authentication is a security measure that requires users to provide two forms of identification before granting access to a system or service. The two factors can involve something the user knows, something the user has or something the user is, such as a password, a security token or biometric authentication. This extra layer of security helps prevent unauthorized access to user accounts even if a password is compromised.

Correct Answer: Hashing

Hashing is the process of transforming a password into a fixed-size value that cannot be transformed back to the original password. Encryption is reversible, encoding is not meant for security, compression reduces the size of data, and obfuscation is used to hide code but is not secure enough for password storage.