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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The __________ is not an FTP command.
a) CWD b) DELE c) DIR d) QUIT
Windows Embedded is designed for consumer devices.
Answer the following statement true (T) or false (F)
The following code is testing a field in the associated form for specific input. Which string is the Case structure looking for in the form? Select Case [Course] Case "CIS 101" lblMessage, Caption = "Prerequisite CIS 100 required"
A. Course B. CIS 100 C. CIS 101 D. Prerequisite CIS 100 required
To move to the right one word, press the ____ key(s).
A. ALT+RIGHT ARROW B. F1 C. CTRL+RIGHT ARROW D. RIGHT+ARROW