Patent ID: 8230253

Claim:
A method implemented in a computer infrastructure having computer executable code tangibly embodied on a computer readable medium being operable to: dynamically adjust quorum requirements for a voting set V of a server cluster, comprising a plurality of servers, to ensure that a response of the server cluster to a client request remains Byzantine fault tolerant when at least one of: a failed server of the server cluster is replaced with at least one new server, such that a total set S of servers that have ever been members of the server cluster is increased; and an existing server is removed from the voting set V, wherein each server comprises a trusted platform module (TPM), the method further comprising the TPM at least one of: maintaining the voting set V; manipulating the voting set V; and servicing requests for the voting set V; the manipulating the voting set V comprises at least one of adding a new server to the server cluster and removing an existing server from the server cluster; and the adding the new server comprises: the new server receiving a cluster identifier which identifies a current voting set and a voting set version number; the new server's TPM checking a validity of the current voting set; the new server synchronizing with the server cluster; the server cluster determining a future voting set; the server cluster making a signed committed decision, which is signed by a quorum of the current voting set, to add the new server to the server cluster; the server cluster sending the signed committed decision to each of the TPMs of the servers of the server cluster; the each of the TPMs validating the signed committed decision; the each of the TPMs performing the signed committed decision; and incrementing the voting set version number.