The TIHI (Trusted Interoperation of Healthcare Information) project addresses a security issue that arises when some information is being shared among
collaborating enterprises, although not all enterprises information is sharable. It assumes that protection exists to prevent intrusion by adversaries through
secure transmission and firewalls. The TIHI system design provides a gateway, owned by the enterprise security officer, to mediate queries and responses.
The problem and our solution applies not only to a healthcare setting, but is equally valid among collaborating enterprises and in many military situations.