Several parameters are defined to describe distributed
storage policy:
1) Backup Reliability: It means file recovery
probability from the rest live nodes while some nodes unavailable, marked as R.
2) Node Dependency: It is the ratio of the minimal
recovery node average number to the total node number, marked as D.
3) File Partition: It describes how many parts a file
is stripped to, marked as P.
4) Space Redundant: It refers to an average replica
number, marked as S.
