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The process of converting information into a form that cannot be understood without a key is called ...
encryption
The term used for the unreadable output of encryption is ...
cipher text
What is the main difference between symmetric and asymmetric encryption?
Symmetric uses one shared key; asymmetric uses a public and private key pair.
Which key must remain secret to maintain the security of asymmetric encryption?
Private key
When a user visits an HTTPS website, what protocol ensures secure communication?
SSL/TLS
Encrypting data with a recipient’s public key ensures __________, because only the recipient can decrypt it.
Confidentiality
Encrypting a hash of a message with a sender’s private key ensures _____ and _____.
Authentication and integrity
If a hacker intercepts a ciphertext, why can’t they easily recover the plaintext?
Because they don’t possess the correct decryption key.
What is one drawback of using only asymmetric encryption in secure communications?
It is computationally slower and less efficient than symmetric encryption.
Tom encrypts a message with Meera’s public key. What ensures that only Meera can decrypt it?
Only Meera’s private key mathematically matches her public key, forming a unique key pair.
A digital certificate is an electronic file that binds an entity’s identity to its __________ key.
public
The Certificate Authority (CA) signs the certificate using its own __________ key.
private
When verifying a certificate, the browser uses the CA’s __________ key to check the signature.
public
Why is a hashing algorithm essential in the digital signing process?
It ensures a fixed-size digest that uniquely represents the original data.
The assurance that a sender cannot deny sending a message is known as __________.
Non-repudiation
During an SSL/TLS handshake, asymmetric encryption is used for what specific purpose?
To securely exchange the session (symmetric) key.
Once the handshake is complete, why does SSL/TLS switch to symmetric encryption?
It is faster and more efficient for bulk data transmission.
What does the server send to the client during an SSL/TLS handshake to prove its identity?
Its digital certificate.
Why is quantum cryptography considered more secure than traditional encryption methods?
Because any attempt to intercept or measure the quantum key changes its state, revealing the presence of an eavesdropper.
How does the use of a digital certificate in SSL/TLS protect users from phishing or fake websites?
It verifies that the website’s public key belongs to a legitimate organization certified by a trusted CA.
Why is quantum cryptography currently impractical for global internet use?
Quantum signals are difficult to transmit over long distances and require specialized infrastructure.
Why is scalability a problem for quantum cryptography networks?
Each connection requires a dedicated optical channel and specialized equipment, making large networks expensive to maintain.
Despite its security benefits, what is one ethical or political drawback of quantum cryptography?
It could give certain governments or corporations exclusive control over unbreakable communications, limiting transparency
BONUS
Suggest why some organizations might delay adopting quantum cryptography even if it becomes commercially available. (3 reasons)
High cost, need for specialized infrastructure, limited range, and compatibility issues with existing systems.