Mod 7 Essay Questions

COM 590

MOD 7 Essay Questions

Chap 13 & 14

Dr. Bal

Chapter 13

1.

Answer. Digital signatures ensure the integrity, authentication, and non-repudiation of a message. A hash value is derived from the original text of the message to generate a digital signature. A hash value is the output of a well-defined mathematical function. Hashing process substantially smaller than the text produces the signature value.

2.

Answer. The formal mechanism for accomplishing this is known as PKI. PKI serves as the trusted third party in a secure transaction. The infrastructure is composed of a CA, a key directory, and associated management rules. The CA function is to verify and resister the identity of users through a RA.

3.

Answer. Key is based on random numbers, whether for a secret key cryptosystem or a public cryptosystem. A good random number source produces numbers that are unknown and unpredictable by adversaries. The importance of random key generation is it will ensure the key could not be guess or just figured out.

4.

Answer. There are two basic types of cryptographic keys: secret key, and public key. The combined use of secret and public key cryptography efficiently underwrites all the authentication, integrity, and secrecy services necessary for most users. The difference between the two is that in secret key cryptography, the same key is used for both encryption and decryption.

5.

Answer. Global commerce relies in trust; the secure message transfer capability provided by cryptography ensures trust. As post-industrial society becomes more and more dependent on networks, the importance of cryptography as a safeguard grows. Cryptography ensures that no one but the authorized recipient can read an electronic communication.

6.

Answer. The integrity of communication process is a primary concerns to organizations. The ability to authenticate senders is also important. It must be possible to authenticate the sender, as well as validate...