CSCI 571 - SECURE WEB COMMUNICATION & WEB SERVER PERFORMANCE QUESTIONS ANSWERED
CORRECTLY LATEST UPDATE 2026
This type of encryption method has the sender and receiver share a key; in other words, the sender
encrypts their message using the same key that the receiver uses to decrypt the message. - Answers
Private Key Encryption
This type of encryption method involves the receiver generating two keys: one used to encrypt
messages, which the receiver would give to the sender, and the other to be kept by the receiver in
order to decrypt the message. - Answers Public Key Encryption
This is one of the first practical, public-key cryptosystems, and is widely used for secure data
transmission - Answers RSA
(True or False?) RSA encryption provides an efficient algorithm for factoring large numbers - Answers
False (no efficient algorithm for this)
How many bits do certificate authorities use in their RSA keys? - Answers 2048
(True or False?) Public/private key encryption methods are not suitable for general purposes. -
Answers True
This type of cipher is one in which the same keys are used to encrypt and decrypt the data. - Answers
Bulk Cipher
(True or False?) Bulk ciphers are fast and can encrypt files of any size - Answers True
(True or False?) Secure communication on the web uses a combination of public key encryption and
conventional one-way ciphers - Answers True
This type of bulk cipher is one of the most used for securing data on the internet, known for its
efficiency and security - Answers AES (Advanced Encryption Standard)
AES is used in most modern encryption protocols, including TLS, with key sizes of _______, ________,
or ________ bits. - Answers 128, 192, 256
This type of bulk cipher has become less popular today due to its slower performance, but is still used
in certain legacy systems; its approach to increasing security involves applying the DES algorithm
three times. - Answers 3DES (Triple Data Encryption Standard)
This type of bulk cipher is an alternative to AES, offering comparable security and performance. -
Answers Camellia
A function that maps a domain of values into a range of numbers - Answers Hash Function (or hash
algorithm)
Given a data item X, H is called a ________ hash function if it is computationally infeasible to find
another data item Y, not equal to X, such that the hash value H(x) equals the hash value H(Y) -
Answers cryptographic
The number produced by applying aa cryptographic hash function to a message. - Answers Message
Digest
Systems combining public key cryptography and message digests. - Answers Digital Signatures
(True or False?) The most widely used bulk ciphers for digital signatures are primarily symmetric
encryption algorithms that focus on security, authentication, and non-repudiation. - Answers False
(asymmetric)
List the three most commonly used asymmetric encryption algorithms - Answers RSA, ECDSA, DSA
(True or False?) Quantum computers pose a significant thread to current cryptographic systems, so
much so that new encryption standards are being developed to withstand quantum attacks. -
Answers True
List the first three finalized standards for quantum encryption standards - Answers CRYSTALS-Kyber,
CRYSTALS-Dilithium, SPHINCS+
An organization that both parties involved in a secure communication trust to verify the authenticity
of digital signatures - Answers Certificate Authority (CA)
A protocol that provides end-to-end security between client and server by *authenticating* both
parties using digital certificates, encrypting communications for *privacy*, and maintaining *message
integrity* through message digests. - Answers SSL/TLS
(True or False?) HTTPS is a combination of HTTP and SSL/TLS - Answers True
What three main things should be considered when estimating server performance? - Answers 1.
Time to deliver request to server
2. Time to obtain result
3. Time to deliver result
CORRECTLY LATEST UPDATE 2026
This type of encryption method has the sender and receiver share a key; in other words, the sender
encrypts their message using the same key that the receiver uses to decrypt the message. - Answers
Private Key Encryption
This type of encryption method involves the receiver generating two keys: one used to encrypt
messages, which the receiver would give to the sender, and the other to be kept by the receiver in
order to decrypt the message. - Answers Public Key Encryption
This is one of the first practical, public-key cryptosystems, and is widely used for secure data
transmission - Answers RSA
(True or False?) RSA encryption provides an efficient algorithm for factoring large numbers - Answers
False (no efficient algorithm for this)
How many bits do certificate authorities use in their RSA keys? - Answers 2048
(True or False?) Public/private key encryption methods are not suitable for general purposes. -
Answers True
This type of cipher is one in which the same keys are used to encrypt and decrypt the data. - Answers
Bulk Cipher
(True or False?) Bulk ciphers are fast and can encrypt files of any size - Answers True
(True or False?) Secure communication on the web uses a combination of public key encryption and
conventional one-way ciphers - Answers True
This type of bulk cipher is one of the most used for securing data on the internet, known for its
efficiency and security - Answers AES (Advanced Encryption Standard)
AES is used in most modern encryption protocols, including TLS, with key sizes of _______, ________,
or ________ bits. - Answers 128, 192, 256
This type of bulk cipher has become less popular today due to its slower performance, but is still used
in certain legacy systems; its approach to increasing security involves applying the DES algorithm
three times. - Answers 3DES (Triple Data Encryption Standard)
This type of bulk cipher is an alternative to AES, offering comparable security and performance. -
Answers Camellia
A function that maps a domain of values into a range of numbers - Answers Hash Function (or hash
algorithm)
Given a data item X, H is called a ________ hash function if it is computationally infeasible to find
another data item Y, not equal to X, such that the hash value H(x) equals the hash value H(Y) -
Answers cryptographic
The number produced by applying aa cryptographic hash function to a message. - Answers Message
Digest
Systems combining public key cryptography and message digests. - Answers Digital Signatures
(True or False?) The most widely used bulk ciphers for digital signatures are primarily symmetric
encryption algorithms that focus on security, authentication, and non-repudiation. - Answers False
(asymmetric)
List the three most commonly used asymmetric encryption algorithms - Answers RSA, ECDSA, DSA
(True or False?) Quantum computers pose a significant thread to current cryptographic systems, so
much so that new encryption standards are being developed to withstand quantum attacks. -
Answers True
List the first three finalized standards for quantum encryption standards - Answers CRYSTALS-Kyber,
CRYSTALS-Dilithium, SPHINCS+
An organization that both parties involved in a secure communication trust to verify the authenticity
of digital signatures - Answers Certificate Authority (CA)
A protocol that provides end-to-end security between client and server by *authenticating* both
parties using digital certificates, encrypting communications for *privacy*, and maintaining *message
integrity* through message digests. - Answers SSL/TLS
(True or False?) HTTPS is a combination of HTTP and SSL/TLS - Answers True
What three main things should be considered when estimating server performance? - Answers 1.
Time to deliver request to server
2. Time to obtain result
3. Time to deliver result
