Describe the CBC rollover problem.
What will be an ideal response?
While CBC is by far the most popular mode of operation, it is not perfect. There is a security property called CBC rollover. Assume that two data blocks P[i] and P[j] encrypt to the same value C. In other words, we have an encryption collision. C[i + 1] = C[j + 1] if P[i + 1] = P[j + 1]. Using XOR property, the attacker will be able to know P[i + 1] = P[j + 1]. In general, encryption collision happens once every 2X/2 blocks with a cipher using an X-bit block size. A given key should not be used to encrypt more than 2X/2 blocks of data to avoid a collision.
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In the structure definition
``` struct StudentRecord { int studentID; char grade; ``` What will be an ideal response?
Which of the following statements is false?
a. A class can directly inherit from class Object. b. It's often much more efficient to create a class by inheriting from a similar class than to create the class by writing every line of code the new class requires. c. If the class you're inheriting from declares instance variables as private, the inherited class can access those instance variables directly. d. A class's instance variables are normally declared private to enforce good software engineering.
When you want to make very specific changes to an object, the Change panel provides precise control over how you modify the object.
Answer the following statement true (T) or false (F)
Painting is the name given to one of the preset ____.
A. tools B. workspaces C. panels D. panel groups