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27 Nov 2020, 13:26
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A cloud computing environment leverages many fundamental technologies. One such technology is virtualization, which allows for a number of virtual machines to share the physical resources of a single physical machine. A large number of physical machines with virtualization could be networked together to form what is known as a cloud environment. A virtual machine that is hosted on a physical machine is often referred to as a guest virtual machine.
The increase in the number of organizations using the same physical host machine for guest virtual machines creates opportunities for certain types of attacks. One example is a side channel attack, in which one virtual machine monitors how another uses shared processor memory to infer sensitive information.
A technique that allows a virtual machine to accommodate increased resource needs or protect against such attacks is migration. Migration is the process of moving a guest virtual machine from one physical host to another. Two migration types considered through experimentation were cloning migration and offline migration. To compare different migration types, a Denial of Service (DoS) scenario was created to increase the resource needs of a host and cause a migration of a virtual machine from one physical host to another.
The increase in the number of organizations using the same physical host machine for guest virtual machines creates opportunities for certain types of attacks. One example is a side channel attack, in which one virtual machine monitors how another uses shared processor memory to infer sensitive information.
A technique that allows a virtual machine to accommodate increased resource needs or protect against such attacks is migration. Migration is the process of moving a guest virtual machine from one physical host to another. Two migration types considered through experimentation were cloning migration and offline migration. To compare different migration types, a Denial of Service (DoS) scenario was created to increase the resource needs of a host and cause a migration of a virtual machine from one physical host to another.
In addition to the two migration types tested earlier, a third type—live migration—was tested in a separate experiment. Its average completion time was 30 seconds, with a fastest time of 24 seconds and a slowest of 114 seconds. For each of the following factors, select Yes if, based on that factor, live migration would be the best choice among the three migration types. Otherwise, select No.
| Yes | No | |
| Lowest average migration time | ||
| Fastest possible migration time | ||
| Lowest maximum migration time |
ShowHide Answer
Official Answer
Lowest average migration time: No
Fastest possible migration time: No
Lowest maximum migration time: No
27 Nov 2020, 13:26
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Official Solution:
Average migration time
• Live migration has an average migration time of 30 seconds. Cloning migration averages around 48 seconds, while offline migration is faster at about 23 seconds. Since live migration does not have the lowest average time, it would not be the best choice based on this factor. NO.
Fastest possible migration time
• The fastest test result for live migration was 24 seconds. For offline migration, it was 21 seconds, and for cloning, about 44.5 seconds. Since offline migration had the fastest possible time overall, live migration would not be the best choice for this factor either. NO.
Lowest maximum migration time
• The longest recorded time for live migration was 114 seconds. This is significantly higher than the maximum times for offline migration (34 seconds) and cloning migration (about 49.5 seconds). Since live migration does not have the lowest maximum migration time, it would not be the best choice based on this factor. NO.
Correct answer:
Lowest average migration time "No"
Fastest possible migration time "No"
Lowest maximum migration time "No"
Bunuel
Average migration time
• Live migration has an average migration time of 30 seconds. Cloning migration averages around 48 seconds, while offline migration is faster at about 23 seconds. Since live migration does not have the lowest average time, it would not be the best choice based on this factor. NO.
Fastest possible migration time
• The fastest test result for live migration was 24 seconds. For offline migration, it was 21 seconds, and for cloning, about 44.5 seconds. Since offline migration had the fastest possible time overall, live migration would not be the best choice for this factor either. NO.
Lowest maximum migration time
• The longest recorded time for live migration was 114 seconds. This is significantly higher than the maximum times for offline migration (34 seconds) and cloning migration (about 49.5 seconds). Since live migration does not have the lowest maximum migration time, it would not be the best choice based on this factor. NO.
Correct answer:
Lowest average migration time "No"
Fastest possible migration time "No"
Lowest maximum migration time "No"
