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 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
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)