US Patent 9667416 Protecting master encryption keys in a distributed computing environment

Protecting master encryption keys by splitting the master encryption key into multiple key shares using a polynomial secret sharing scheme, and storing one share in a remote management server and the other shares in managed devices located on one or more secure networks. To reconstruct the master encryption key, a managed device obtains the remote management server share and combines it with its local share. Master encryption keys may be obtained without an administrator's password, thus supporting unattended startup of appliances. The remote management server may alert a system administrator upon release of the remote management key share, or request approval prior to releasing the remote management key share.