Information secure protocol for mobile proactive secret sharing with near-optimal resilience

A computer program product for mobile proactive secret sharing, the computer program product comprising:

• a non-transitory computer-readable medium having executable instructions encoded thereon, such that upon execution of the instructions by one or more processors, the one or more processors perform operations of:
• initializing a First protocol to distribute a block of secret data among a set of servers comprising n servers of a synchronous network, wherein the block of secret data comprises a plurality of shares of data, wherein each server in the set of servers holds one share of data encoding the block of secret data, and wherein the plurality of shares of data is transmitted electronically via a secure, authenticated broadcast channel;
• initializing at least one Second protocol to protect against an adversary that attempts to corrupt the set of servers, wherein during a Second protocol the set of servers periodically refreshes its plurality of shares of data such that each server holds a new share of data that is independent of the previous share of data, wherein the set of servers engaged in a Second protocol and the number of servers, n, can change at each redistribution;
• and
• periodically erasing, by each server, the plurality of shares of data to preserve security against the adversary,
• wherein the at least one Second protocol comprises one of a statistically secure version and a perfect security version for security against the adversary, the perfect security version having a threshold for corruption that is lower than that of the statistically secure version,
• wherein the at least one Second protocol is initiated as the perfect security version, then the threshold for corruption is raised in the statistically secure version using statistically secure virtualization.

A computer implemented method for mobile proactive secret sharing, the method comprising an act of:

• causing one or more processers to execute instructions encoded on a non-transitory computer-readable medium, such that upon execution, the one or more processors perform operations of:
• initializing a First protocol to distribute a block of secret data among a set of servers comprising n servers of a synchronous network, wherein the block of secret data comprises a plurality of shares of data, wherein each server in the set of servers holds one share of data encoding the block of secret data, and wherein the plurality of shares of data is transmitted electronically via a secure, authenticated broadcast channel;
• initializing at least one Second protocol to protect against an adversary that attempts to corrupt the set of servers, wherein during a Second protocol the set of servers periodically refreshes its plurality of shares of data such that each server holds a new share of data that is independent of the previous share of data, wherein the set of servers engaged in a Second protocol and the number of servers, n, can change at each redistribution;
• and
• periodically erasing, by each server, the plurality of shares of data to preserve security against the adversary,
• wherein the at least one Second protocol comprises one of a statistically secure version and a perfect security version for security against the adversary, the perfect security version having a threshold for corruption that is lower than that Qf the statistically secure version,
• wherein the at least one Second protocol is initiated as the perfect security version, then the threshold for corruption is raised in the statistically secure version using statistically secure virtualization.