Briefly describe DES and its variants.
What will be an ideal response?
The data encryption standard (DES), dating back to 1976, is a cipher selected as an official federal information processing standard (FIPS) for the United States. It is certainly the most widely used cipher internationally. It uses fixed 64-bit blocks and 64-bit keys with 8- bits parity. The 54-bit key (64 - 8) is generally considered too small, and some DES keys have been broken in less than 24 hours. Most DES users now use Triple DES (3DES). In 3DES, data is encrypted with DES to produce ciphertext, and then a second key is used to "decrypt" the ciphertext. Finally, the data is encrypted again with either the original key (two-key 3DES) or with a third key (three-key 3DES). 3DES is secure but slow. A quicker alternative is DES-X, which increases the key size by XORing extra key material before and after DES.
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Use the Java IDL compiler to process the interface. Inspect the definition of the signatures for the methods pairIn and readPair in the generated Java equivalent of the IDL interface. Look also at the generated definition of the holder method for the value argument for the methods pairIn and readPair. Now give an example showing how the client will invoke the pairIn method, explaining how it will acquire the value returned via the second argument.
What will be an ideal response?
Twitter has become a primary means for disseminating breaking news stories
Indicate whether the statement is true or false
When a ________ within a form or report is deleted, only that object is deleted, not the actual form or report
A) button B) cursor C) tab D) data type
The region of an active Microsoft Excel sheet that is sent to the printer is known as the _________. A. print space B. print preview C. print area D. print domain
Fill in the blank(s) with the appropriate word(s).