The only solution to the latency issue is to have you processing "machine" on the cloud-provider's infrastructure. At that point you surrender any security as that machine would necessarily have the key(s) to decrypt your data.
Otherwise you can use cloud for secure storage so long as it is encrypted at your end using a key not known to the storage provider, which is a good options for some situations (e.g. off-site backup).
Biting the hand that feeds IT
