Thank you for the opportunity to help you with your question!
Encrption has one fundamental reason,for privacy and to be secure.This is accompanied with the benefits such as finance and data security.To mainatain high level of security using encryption,
it is recommended to keep on frequently changing your encryption keys,due to the following:
1.Encryption does not protect against a malicious data adminstrator, who may gain elevated privilleges by guessing user password. They can then delete or export data despite encrption. Frequent change of keys limits such like attacks
2.Changing involves changing any case of prediction does minimizing chances of key prediction.
Possible attacks include acess ,deleting and export of data
Is reccommended to change at least once anually.
Please let me know if you need any clarification. I'm always happy to answer your questions.
Jul 1st, 2015
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