Explanation:An one-way function is a function which a computer can calculate quickly, but whose reversal would last months or years. An one-way function with back door can be reversed with the help of a couple of additional information (the back door), but scarcely without this information. The information for the back door is contained in the private Key. 9. Which is the largest disadvantage of the symmetric Encryption?
A. More complex and therefore more time-consuming calculations
B. Problem of the secure transmission of the Secret Key
C. Less secure encryption function
D. Isn’t used any more
Answer:A
Explanation:An one-way function is a function which a computer can calculate quickly, but whose reversal would last months or years. An one-way function with back door can be reversed with the help of a couple of additional information (the back door), but scarcely without this information. The information for the back door is contained in the private Key. 9. Which is the largest disadvantage of the symmetric Encryption?
A. More complex and therefore more time-consuming calculations B. Problem of the secure transmission of the Secret Key C. Less secure encryption function D. Isn’t used any more
Explanation:As there is only one key in the symmetrical encryption, this must be known by both sender and recipient and this key is sufficent to decrypt the secret message. Therefore it must be exchanged between sender and receiver in such a manner that an unauthorized person can in no case take possesion of it. 10. Which is the principle of the encryption using a key?