Network Security and Cryptography Quiz

<p>By ensuring authorized access only to sensitive data (D)</p> Signup and view all the answers

<p>Timeliness (A)</p> Signup and view all the answers

<p>To transform a message into an unintelligible format (B)</p> Signup and view all the answers

<p>The decryption key (A)</p> Signup and view all the answers

<p>They can be personalized by adjusting keys (D)</p> Signup and view all the answers

<p>The sender and receiver share the same decryption key (D)</p> Signup and view all the answers

<p>The absence of data contamination (D)</p> Signup and view all the answers

<p>Symmetric-key uses one key while asymmetric uses two keys (D)</p> Signup and view all the answers

<p>DDoS attack (B)</p> Signup and view all the answers

<p>It results in an encrypted ciphertext (C)</p> Signup and view all the answers

<p>Public Key Certificate (B)</p> Signup and view all the answers

<p>When they are in the same room (A)</p> Signup and view all the answers

<p>X.509 (C)</p> Signup and view all the answers

<p>Transferring keys outside the digital network (C)</p> Signup and view all the answers

<p>An organization like Bob's employer (D)</p> Signup and view all the answers

<p>To verify the integrity of the message using a secret key (C)</p> Signup and view all the answers

<p>It is used to compute the correct HMAC for comparison (A)</p> Signup and view all the answers

<p>It is used to secure a single episode of communication (C)</p> Signup and view all the answers

<p>To ensure the session key remains secret from adversaries (C)</p> Signup and view all the answers

<p>They ensure the security of the session key establishment (A)</p> Signup and view all the answers

<p>Session keys improve speed by being symmetric keys (A)</p> Signup and view all the answers

<p>Public-key ciphers use distinct public keys for identification (C)</p> Signup and view all the answers

<p>The receiver can compute the correct HMAC for comparison purposes (D)</p> Signup and view all the answers

<p>56 bits (C)</p> Signup and view all the answers

<p>Using three separate DES operations (B)</p> Signup and view all the answers

<p>Higher key lengths (C)</p> Signup and view all the answers

<p>One key is for encryption and a related key is for decryption. (B)</p> Signup and view all the answers

<p>The private key remains confidential with the owner (C)</p> Signup and view all the answers

<p>DES-key3 (D)</p> Signup and view all the answers

<p>128 bits (C)</p> Signup and view all the answers

<p>The decryption key is publicly distributed (B)</p> Signup and view all the answers

<p>Discrete logarithm problem (B)</p> Signup and view all the answers

<p>1024 bits (D)</p> Signup and view all the answers

<p>To verify authenticity and data integrity (B)</p> Signup and view all the answers

<p>It exposes deliberate message corruption. (C)</p> Signup and view all the answers

<p>Message digest (B)</p> Signup and view all the answers

<p>It is always smaller than the original message. (B)</p> Signup and view all the answers

<p>Hash collision (B)</p> Signup and view all the answers

<p>They expose errors from noisy links. (B)</p> Signup and view all the answers

<p>A symmetric key must be kept secret for each entity pair. (C)</p> Signup and view all the answers

<p>$N(N - 1)/2$ (D)</p> Signup and view all the answers

<p>One public key is sufficient for authentication and confidentiality. (B)</p> Signup and view all the answers

<p>They must be kept secret and not shared publicly. (C)</p> Signup and view all the answers

<p>Symmetric keys are more complex due to the need for individual pairs' keys. (B)</p> Signup and view all the answers

<p>To provide nonrepudiation similar to a written signature (D)</p> Signup and view all the answers

<p>Minimal management as they do not need to be kept secret. (B)</p> Signup and view all the answers

<p>To authenticate the sender. (C), To ensure data integrity. (D)</p> Signup and view all the answers

<p>It requires secure channels for distribution. (A)</p> Signup and view all the answers

<p>160 bits (B)</p> Signup and view all the answers

<p>It is known only to the sender and the receiver to generate a MAC (B)</p> Signup and view all the answers

<p>Every pair of entities requires a unique key. (B)</p> Signup and view all the answers

<p>Using a session key establishment protocol. (C)</p> Signup and view all the answers

<p>HMAC applies a cryptographic hash to a message and a secret value (A)</p> Signup and view all the answers

<p>Short-lived keys. (B)</p> Signup and view all the answers

<p>They both produce fixed length message digests (B)</p> Signup and view all the answers

<p>It must ensure the session key is known only to the participants. (D)</p> Signup and view all the answers

<p>It verifies message integrity and authenticity (B)</p> Signup and view all the answers

<p>Session keys are derived from longer-lived pre-distributed keys. (B)</p> Signup and view all the answers

<p>MD5 (D)</p> Signup and view all the answers

<p>HMAC is dependent on the secret key for computation. (C)</p> Signup and view all the answers

<p>Public-key ciphers utilize a pair of keys for each participant. (D)</p> Signup and view all the answers

<p>Both incorporate a cryptographic hash function (A)</p> Signup and view all the answers

<p>The receiver can generate a valid HMAC for received messages. (A)</p> Signup and view all the answers

<p>The identity of the signer (C)</p> Signup and view all the answers

<p>To verify identities and issue public key certificates (A)</p> Signup and view all the answers

<p>They lack a secure method to encrypt the key and authenticate each other (B)</p> Signup and view all the answers

<p>A way to trust certificates signed by new CAs (C)</p> Signup and view all the answers

<p>The private key of the entity being certified (A)</p> Signup and view all the answers

<p>A chain of CA-signed certificates starting from a known CA (C)</p> Signup and view all the answers

<p>Which cryptographic hash and cipher are used (A)</p> Signup and view all the answers

<p>Maintaining the confidentiality and authenticity of the keys (D)</p> Signup and view all the answers

<p>To divide a network into trusted and less-trusted zones (A)</p> Signup and view all the answers

<p>An area where external users can access certain services without affecting the internal network (D)</p> Signup and view all the answers

<p>There should be no alternate routes bypassing the firewall (A)</p> Signup and view all the answers

<p>By maintaining a table of IP addresses and port numbers (B)</p> Signup and view all the answers

<p>A tuple containing source and destination IP addresses and their respective port numbers (B)</p> Signup and view all the answers

<p>Three zones: internal network, DMZ, and external Internet (A)</p> Signup and view all the answers

<p>A hardware device specifically designed to implement firewall rules (D)</p> Signup and view all the answers

<p>Wireless signal enhancement (D)</p> Signup and view all the answers

<p>To enhance authentication, message integrity, and confidentiality for Wi-Fi networks (C)</p> Signup and view all the answers

<p>WPA2 is synonymous with 802.11i. (A)</p> Signup and view all the answers

<p>Pre-Shared Key (PSK) mode (B)</p> Signup and view all the answers

<p>A long password entered by the user (A)</p> Signup and view all the answers

<p>It verifies user identities before granting access to the network. (A)</p> Signup and view all the answers

<p>They both provide mechanisms for encryption and authentication. (B)</p> Signup and view all the answers

<p>To monitor and control incoming and outgoing network traffic. (D)</p> Signup and view all the answers

<p>Different addresses (B)</p> Signup and view all the answers

Protecting network resources from unauthorized access, use, disclosure, disruption, modification, or destruction.

Ensuring that only authorized parties can access a message's contents. Encryption is key.

Ensuring that data is not altered or corrupted by unauthorized parties.

Verifying the source of a message; guaranteeing its creation by the claimed sender.

Verifying the identity of a user or entity.

Using mathematical algorithms to protect sensitive information from unauthorized access.

Transforming plaintext into ciphertext, making it unreadable without the decryption key.

Using the same key to encrypt and decrypt data, both parties need the key.

Reversing the encryption process, transforming ciphertext back to readable plaintext.

An algorithm used for encryption or decryption, transforming data according to a specific rule.

A one-way function that generates a unique fingerprint (hash) for a piece of data.

A secret value that controls encryption and decryption processes.

Keys provide flexibility and security, allowing users to change encryption/decryption methods and control access to data.

Encryption methods that use two related keys: a public key for encryption and a private key for decryption.

Another name for public key ciphers, emphasizing that the encryption and decryption keys are different.

It's used to encrypt messages that only the owner of the corresponding private key can decrypt.

The private key is kept secret and cannot be deduced from the public key, ensuring only the owner can decrypt messages.

A key is a secret piece of information used to encrypt and decrypt data, ensuring the security of communication.

The process of verifying identities and binding them to keys outside of the network, such as in physical meetings or through trusted administrators.

A digitally signed statement that binds a public key to an identity, verifying the ownership of that key.

A widely used standard for public key certificates, defining the structure and content of certificates.

The process of distributing public keys beforehand to enable secure communication between parties.

Public key certificates are used to verify the authenticity of a public key and ensure its association with a specific entity.

A public-key cipher that like RSA relies on a mathematical problem, the discrete logarithm problem, for which no efficient solution has been found, and requires keys of at least 1024 bits.

A function that generates a message digest (checksum) from a message, exposing any tampering.

The output of a cryptographic hash function, a fixed-length string representing the message, used to verify integrity.

Cryptographic checksums are used to detect deliberate corruption of messages by an adversary. They work like a digital fingerprint, providing a unique identifier for the message that can be used to verify its integrity.

Because the security of a cryptographic hash function relies on the difficulty of finding collisions (different messages producing the same digest). This means that anyone should be able to verify the message digest, making it public knowledge.

Collisions occur when different input messages produce the same message digest. While collisions are possible, a good hash function makes them extremely rare.

While a regular checksum detects random bit errors, a cryptographic checksum is designed to detect deliberate corruption of messages, making it more robust against malicious tampering.

A type of message authentication code (MAC) that uses a hash function and a secret key to verify the integrity and sender of a message. It combines the message and secret key using a hash function, resulting in a unique digest.

The HMAC itself is transmitted along with the message, but the secret value used to calculate it is kept secret. This ensures that only someone with the secret value can verify the HMAC.

A temporary, symmetric-key used to secure a single communication session between two parties. It is generated for each individual session and discarded after the session ends.

A protocol used by communicating parties to securely establish a session key. This is important as the session key itself needs to be protected from eavesdropping or manipulation.

Long-lived keys used to secure the session key establishment protocol. They are usually kept secure and are used for a longer period of time, unlike session keys.

Session keys are short-lived, specific to individual communication sessions, and established using pre-distributed keys, which are longer-lived and provide security for the session key establishment process.

Through a session key establishment protocol that utilizes pre-distributed keys. This protects the session key itself, ensuring secure communication in each session.

A mathematical function that transforms data into a fixed-length string (digest), used to verify data integrity and authenticity.

Common cryptographic hash algorithms. MD5 outputs a 128-bit digest, while SHA-1 outputs a 160-bit digest.

A digest encrypted with a public key algorithm using the private key, used to verify the sender's identity and prevent repudiation.

An authenticator generated using a hash-like function with a secret key known only to the sender and receiver, used to verify message integrity and authenticity.

A MAC that combines a hash function like MD5 or SHA-1 with the message and secret key, creating a unique digest for authentication.

Encryption method using a public key to encrypt data, and a private key to decrypt it, ensuring only the intended recipient can read the message.

Ensuring that a sender cannot deny having sent a message, provided by digital signatures.

A trusted entity that verifies identities and issues digital certificates containing public keys. Individuals and organizations rely on CAs to confirm the authenticity of digital certificates.

A series of certificates linked together. Each certificate is signed by the preceding one, so if the first certificate is trusted, all subsequent certificates in the chain are also considered valid.

Pre-distribution is necessary because it allows parties to securely communicate using secret-key ciphers. Without it, parties would need a secure channel to exchange their keys, which can be a challenge.

It's a protocol used by parties to securely generate a session key. This protocol relies on pre-distributed keys to ensure the safety of the session key exchange.

A standard providing authentication, message integrity, and confidentiality for Wi-Fi networks at the link layer. Often referred to as WPA2.

A shared secret key established after successful authentication in 802.11i, used for secure communication between a wireless device and Access Point.

Authentication mode in 802.11i where a pre-shared passphrase is used to derive the Pairwise Master Key, providing simpler but less secure setup for home networks.

A server used in 802.11i for authenticating users and establishing a secure connection, offering stronger security than Personal Mode.

A system that controls network traffic between a protected site and the external network, preventing unauthorized access and protecting sensitive data.

To filter and control network traffic, preventing unauthorized access, malware, and data breaches, acting as a barrier between a protected site and the external network.

A common implementation of the IEEE 802.11i standard, providing robust security for wireless networks.

WPA2 is a trademark of the Wi-Fi Alliance, certifying product compliance with the IEEE 802.11i security standard, essentially synonymous with 802.11i in practice.

The process of distributing secret keys to each pair of entities that want to communicate securely. This involves distributing N(N-1)/2 keys for N entities, making it challenging for large networks.

Distributing only public keys to entities, allowing secure communication without needing separate keys for each pair. This simplifies management as only one public key per entity is required.

A security protocol where one entity challenges another with a random value, and the responding entity uses a secret key to generate a response. This verifies the authenticity of the other entity.

A protocol where participants exchange public keys and use them to verify each other's identities. This eliminates the need for pre-shared secret keys.

A requirement for both parties to have synchronized clocks or use a trusted third party to assure the authenticity of messages by verifying timestamps.

A protocol where each party verifies its own timestamp against its own clock, removing the dependency on synchronized clocks or a trusted third party for verification.

Because every pair of entities requires a unique secret key, the number of keys grows rapidly with the number of entities in the system. This makes management and distribution of the keys a logistical challenge.

It requires only one public key per entity, simplifying key management. This dramatically reduces the number of keys needed compared to symmetric key pre-distribution.

A firewall acts as a barrier between a trusted network (internal) and a less-trusted network (external), controlling access and preventing unauthorized entry.

Firewalls can create multiple levels of trust within a network. A common arrangement involves three zones: internal network, DMZ (Demilitarized Zone), and external network (Internet).

Firewalls analyze network traffic based on various factors, including IP addresses, TCP/UDP ports, and other information, to determine whether to allow or block access.

Each entry in the firewall's rule table is a 4-tuple, consisting of source and destination IP addresses, and source and destination TCP/UDP ports. This helps to pinpoint specific network connections.

A firewall's effectiveness depends on preventing any unauthorized access or bypasses. All traffic should go through the firewall.

Firewalls are typically implemented as dedicated hardware appliances or integrated into routers. They can also be software-based and run on individual machines.

A firewall protects a network, while a personal firewall protects a single computer or device from unauthorized access.

A firewall's effectiveness is contingent on proper configuration, regular updates, and understanding of potential vulnerabilities.