Cryptography is the practice and study of techniques for secure communication in the presence of third parties
(called adversaries.) More generally, it is about constructing and analyzing protocols that overcome the
influence of adversaries and that are related to various aspects in information security such as data
confidentiality, data integrity, authentication, and non-repudiation. Modern cryptography intersects the
disciplines of mathematics, computer science, and electrical engineering. Applications of cryptography include
ATM cards, computer passwords, and electronic commerce.Basic example to understand how cryptography works is given below:
SECURE (plain text)
+1(+1 next letter, for example, the letter ““T”” is used for ““S”” to encrypt.)
TFDVSF (encrypted text)
+=logic=> Algorithm
1=Factor=> Key
Which of the following choices is true about cryptography?
A.
Algorithm is not the secret, key is the secret.
B.
Symmetric-key algorithms are a class of algorithms for cryptography that use the different cryptographic
keys for both encryption of plaintext and decryption of ciphertext.
C.
Secure Sockets Layer (SSL) use the asymmetric encryption both (public/private key pair) to deliver the
shared session key and to achieve a communication way.
D.
Public-key cryptography, also known as asymmetric cryptography, public key is for decrypt, private key is for
encrypt.
The correct answer is A. In SSL Asymmetric encryption is only used to exchange the shared key. Once the shared key is exchanged the remainder of the session uses symmetric encryption.
I still believe C is the correct answer. Technically it’s not wrong, it does achieve a way for communication to take place (eventually). Answer A however is still too highly disputed since some entities such as the NSA keep their algorithms secret as per their defense in depth strategy.
A