Exam 2: Symmetric Encryption and Message Confidentiality

The _________ algorithm takes the ciphertext and the same secret key and produces the original plaintext.

Random numbers play an important role in the use of encryption for various network security applications.

The ________ source is drawn from the physical environment of the computer and could include things such as keystroke timing patterns, disk electrical activity, mouse movements, and instantaneous values of the system clock.

The principal drawback of 3DES is that the algorithm is relatively sluggish in software.

The three most important symmetric block ciphers are: triple DES (3DES), the Advanced Encryption Standard (AES), and the ___________ .

A PRNG takes as input a fixed value called the ________ and produces a sequence of output bits using a deterministic algorithm.

The primary advantage of a stream cipher is that stream ciphers are almost always faster and use far less code than do block ciphers.

Many symmetric block encryption algorithms including DES have a structure first described by _________ of IBM in 1973.

The security of symmetric encryption depends on the secrecy of the algorithm, not the secrecy of the key.