Chapter 8 End of Book Questions CSCI 290
Which of the following methods uses a variable-length symmetric key?
A Blowfish
Which of the following most accurately defines encryption?
A Changing a message so it can only be easily read by the intended recipient.
Why is binary mathematical encryption not secure?
A It does not change letter or word frequency
What advantage does a symmetric key system using 64-bit blocks have?
A It is fast
Which of the following is used by PPTP to encrypt packets?
A Microsoft Point-to-Point Encryption
Which of the following is most true regarding new encryption methods?
A Never use them until they have been proven
Which of the following is the oldest protocol used by VPN?
A PPTP
What is PGP?
A Pretty Good Privacy, a public key encription method
Which of the following is most true regarding binary operations and encryption?
B They can form a part of viable encryption methods
Which of the following is a symmetric key system using 64-bit blocks?
B DES
What type of encryption uses different keys to encrypt and decrypt the message?
B Public key
What size key does a DES system use?
C 56 bit
Which of the following is the oldest encryption method discussed in this text?
C Caesar Cipher
Which of the following is an encryption method using two or more different shifts?
C DES
Which of the following is most likely to be true of an encryption method advertised as unbreakable?
C It is likely to be exaggerated
Which binary mathematical operation can be used for a simple encryption method?
C XOR
What should you be most careful of when looking for an encryption method to use?
D How long the algorithm has been around
What is the main problem with simple substitution?
D It maintains letter and word frequency
Which of the following methods is available as an add-in for most e-mail clients?
D PGP
Which of the following is most true regarding certified encryption methods?
D There is no such thing as certified encryption
