ABSTRACT
Online collaboration in its general form is the computation of some function over inputs that are distributed among different participants (i.e., organizations, individuals, etc.). As an example, consider an online auction: The inputs are the bidder’s bid values and the outcome is the winner of the auction along with the required payment. A simple way to achieve such collaborations is to collect all of the inputs at a single location and to compute the desired outcome. However, this poses many confidentiality and privacy concerns, including (1) the shared information may be used against a participant at a later time; (2) sharing information makes security vulnerabilities greater because break-ins, spyware, and insider threats at one of the collaborator’s sites will now reveal other collaborators’ information; and (3) it may be illegal to share some of the participant’s inputs (e.g., medical records cannot be shared under HIPAA legislation).
