Which type of RAID configuration requires minimum six drives?

Which type of RAID configuration requires minimum six drives?

• RAID 60 (RAID 6 + 0)
• RAID 50 (RAID 5 + 0)
• RAID 100 (RAID 10+0)
• RAID 6 

 

EXPLANATION

RAID 50, also called RAID 5+0, combines the straight block-level striping of RAID 0 with the distributed parity of RAID 5.[3] As a RAID 0 array striped across RAID 5 elements, minimal RAID 50 configuration requires six drives.

SOURCE

https://en.wikipedia.org/wiki/Nested_RAID_levels

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When it comes to associative memory, how does the memory locate the address of the data?

When it comes to associative memory, how does the memory locate the address of the data?

• The address of the data is supplied by the users
• The address of the data is generated by the CPU
• The data are accessed sequentially
• There is no need for an address, the data is used as an address 

 

EXPLANATION

Associative memory is memory capable of determining whether a given datum (the search word) is contained in one of its addresses or locations. Associative memory  is also referred to as content-addressable memory.
Unlike standard computer memory (random access memory or RAM) in which the user supplies a memory address and the RAM returns the data word stored at that address, associative memory is designed such that the user supplies a data word and the computer searches its entire memory to see if that data word is stored anywhere in it.

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What is the non-linear function that made DES cryptography so strong?

What is the non-linear function that made DES cryptography so strong?

• Trick question, DES is fully linear
• Swapping 4 bytes (left and right) after every round
• Expansion & Contraction algorithms
• 16 rounds of S-Box lookups 

 

EXPLANATION

The genius of Horst Feisel's cipher was in the use S-Boxes for a non-linear lookup function based on the bit values of the ciphertext within each round. Operating on only 1/2 the ciphertext per round, the 48 expanded bits are chopped into 6-bit inputs across the 8 S-Boxes, with each 6-bit input performing a row/table lookup to yield 4 bits of output.  Without this non-linear function, DES would have been linear, and thus very weak.
This design is even more impressive when you consider that the process ran the same forwards and backwards for encrypt/decrypt, and was optimized for hardware.  While met with great suspicion when introduced, the Data Encryption Standard proved worthy of the trust provided it, weathering every attack except Moore's Law and time, which ultimately led to its obsolescence due to brute force attacks.  40 years later, the field of cryptography, and the fabric of the Internet and digital commerce, owes much to the knowledge we gained regarding cryptanalysis and ciphers from this legacy

SOURCE

https://en.wikipedia.org/wiki/Data_Encryption_Standard#The_Feistel_.28F.29_function

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Ubuntu releases are usually nicknamed after animals. Which of these was not a release nickname?

Ubuntu releases are usually nicknamed after animals. Which of these was not a release nickname?

• Avid Aardvark
• Hoary Hedgehog
• Jaunty Jackalope
• Warty Warthog 

 

EXPLANATION

The only one of these ridiculous names that isn't a real thing is Avid Aardvark.

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What version of Office are you using when the installation folder is Office14?

What version of Office are you using when the installation folder is Office14?

• Office 2014
• Office 2010
• Office 2013
• Office 2016 

 

EXPLANATION

Microsoft started office at version one and put the version number at the end of the folder. Beginning with Office 95, Microsoft started naming the versions after the years in which they were released, but they kept using the version number for the program folder.

SOURCE

http://www.ryadel.com/en/microsoft-office-default-installation-folders-versions/

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