Protecting data in the cloud
Cloud computing — outsourcing computational tasks over the Internet — could give home-computer users unprecedented processing power and let small companies launch sophisticated Web services without building massive server farms.But it also raises privacy concerns. A bank of cloud servers could be running applications for 1,000 customers at once; unbeknownst to the hosting service, one of those applications might have no purpose other than spying on the other 999.Encryption could make cloud servers more secure. Only when the data is actually being processed would it be decrypted; the results of any computations would be re-encrypted before they’re sent off-chip.In the last 10 years or so, however, it’s become clear that even when a computer is handling encrypted data, its memory-access patterns — the frequency with which it stores and accesses data at different memory addresses — can betray a shocking amount of private information. At the International Symposium on Computer...