Cryptography Module 5 Review Questions

<p>Diffie-Hellman (C)</p> Signup and view all the answers

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

<p>To limit data compromise in case of key discovery (A)</p> Signup and view all the answers

<p>Physically delivering it to the recipient (C)</p> Signup and view all the answers

<p>To minimize the effort involved in master key distribution (D)</p> Signup and view all the answers

<p>The balance between security and network capacity (D)</p> Signup and view all the answers

<p>To control how automatically distributed keys are used (C)</p> Signup and view all the answers

<p>Symmetric and asymmetric encryption (B)</p> Signup and view all the answers

<p>RSA algorithm (B)</p> Signup and view all the answers

<p>Through public announcement (B)</p> Signup and view all the answers

<p>To securely exchange a key for symmetric encryption (B)</p> Signup and view all the answers

<p>The user's private key is compromised (D)</p> Signup and view all the answers

<p>To certify and manage public keys through certificates (D)</p> Signup and view all the answers

<p>They confirm the authenticity of a public key (C)</p> Signup and view all the answers

<p>A structure for organizing and managing keys (A)</p> Signup and view all the answers

<p>A key used for a single encryption session (D)</p> Signup and view all the answers

<p>Enhanced security through multiple algorithms (C)</p> Signup and view all the answers

<p>To ensure only valid certificates are used (C)</p> Signup and view all the answers

<p>To deliver a key to parties wanting to encrypt data (D)</p> Signup and view all the answers

<p>They must share the same key and protect it from attackers (B)</p> Signup and view all the answers

<p>Using a public key to encrypt the symmetric key (A)</p> Signup and view all the answers

<p>It enhances overall security of communications (A)</p> Signup and view all the answers

<p>The lifespan and expiry of the key (C)</p> Signup and view all the answers

<p>Utilizes both symmetric and asymmetric encryption methods (A)</p> Signup and view all the answers

<p>Physical delivery via postal services (A)</p> Signup and view all the answers

<p>They are digitally signed by a trusted certification authority (D)</p> Signup and view all the answers

<p>The user's private key is potentially compromised (B)</p> Signup and view all the answers

<p>Securely exchanging cryptographic keys (B)</p> Signup and view all the answers

<p>Intercepting and modifying communications without being detected (A)</p> Signup and view all the answers

<p>To provide public-key encryption and create digital signatures (D)</p> Signup and view all the answers

<p>To transmit confidential data securely (D)</p> Signup and view all the answers

<p>Symmetric key cryptosystem (A)</p> Signup and view all the answers

<p>To confirm the origin and integrity of a message (C)</p> Signup and view all the answers

<p>SHA-256 (D)</p> Signup and view all the answers

<p>A code attached to a message that guarantees its source and integrity (D)</p> Signup and view all the answers

<p>To compress the message into a fixed-sized fingerprint (A)</p> Signup and view all the answers

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

<p>By digitally signing the message (C)</p> Signup and view all the answers

<p>Enhanced security through key separation (B)</p> Signup and view all the answers

<p>Key-only attack (D)</p> Signup and view all the answers

<p>It is used to sign the message (C)</p> Signup and view all the answers

<p>Symmetric cryptosystem (B)</p> Signup and view all the answers

Method of sharing the same secret key for encryption and decryption between parties.

Cryptographic keys used only once for secure communication; preventing repeated use and protecting sensitive data if a key is compromised.

A system of managing cryptographic keys in multiple levels; often involving a master key to manage other keys.

The period during which a session key is valid and used for encryption/decryption.

A unique identifier used to categorize and track cryptographic keys.

A combined approach using both symmetric and asymmetric encryption methods.

Publicly sharing a cryptography key that is used for encrypting data sent to its holder.

Canceling a digital certificate to prevent its further use and maintain security.

A method for securely exchanging secret keys over an insecure channel.

An entity that issues and manages digital certificates, verifying public keys.

A digital document that confirms the authenticity of a public key.

A structured way of organizing and managing cryptographic keys.

A temporary key used for a single encryption session.

A key used to generate other keys, often for session keys.

The process of delivering a key to parties who want to exchange data securely. Secure key distribution is crucial for encrypting and decrypting information.

In encryption, the same secret key is used for both encrypting and decrypting data. This requires the secure exchange of the same key to both parties.

Two separate keys are used: a public key for encryption, and a private key for decryption. Public keys are freely shared, private keys are kept secret.

The practice of changing encryption keys regularly. This enhances security by limiting the damage from compromised keys.

Digital certificates used to verify the identity of entities in a network.

Ways to share public keys securely. Examples include public announcements, public-key authorities, public-key certificates.

A type of attack where an attacker intercepts communication between two parties, impersonating one of them to steal sensitive information. This type of hacking is particularly dangerous in key exchange processes.

An asymmetric cryptographic system used for both encryption and digital signatures. It uses a public and private key pair, but not the same algorithms as RSA.

To ensure the confidentiality, integrity, and availability of information. This means protecting data from unauthorized access, modification, or disruption.

A type of cryptography where the same key is used for both encryption and decryption. This key must be shared securely between the communicating parties.

To verify the authenticity and integrity of a message or document. It guarantees that the message was sent by the claimed sender and hasn't been tampered with.

A one-way mathematical function that transforms data into a fixed-length hash value. SHA-256 is a widely used standard in digital signatures, creating a unique fingerprint for the message.

The process of transforming plaintext into ciphertext, making it unreadable without the decryption key.

Uses a single secret key for both encrypting and decrypting data. Both parties need the same key.

Uses two separate keys: a public key for encryption and a private key for decryption. Only the private key can decrypt data encrypted with the corresponding public key.

A unique random number generated for each message to prevent replay attacks. It ensures that a message hasn't been sent before and guarantees its freshness.

To securely distribute cryptographic keys between parties without revealing them to eavesdroppers. It enables secure communication without sharing keys directly.

Public key cryptography provides enhanced security through key separation, where the private key is kept secret and the public key is shared. This ensures that only the intended recipient can decrypt encrypted messages and verify digital signatures.

A digital signature is a code attached to a message that guarantees its source and integrity. It verifies that the message is genuine and hasn't been tampered with.

In digital signatures, a hash function compresses the message into a fixed-sized fingerprint (hash). This hash is signed and used for verification. If the message changes, the hash will change, revealing tampering.

A key-only attack aims to determine the signer's private key using only their public key. The attacker attempts to deduce the private key based on the public key's structure and mathematical properties.

Digital signatures provide non-repudiation by ensuring that the sender cannot deny having signed the message. It verifies the sender's identity and prevents them from claiming they didn't sign it.

The inverse cryptographic transformation in a cryptosystem is the process of decryption. It uses the appropriate key (either private or shared) to convert encrypted data back into its original form.

A symmetric cryptosystem uses the same key for both encryption and decryption. This means the sender and receiver must share the same secret key to communicate securely.

A cryptographic transformation is a process that converts input data into output data using a cryptographic key. This includes both encryption and decryption.