Systems and methods for implementing source transparent email gateways

摘要

Methods and arrangements for implementing new email handling policies in gateway logic that is inserted upstream of the existing email system (which may or may not have an existing email gateway). By inserting the gateway logic upstream of the existing email system, it is unnecessary to reconfigure existing email handling logic since the remainder of the email system downstream of the newly inserted gateway logic is substantially undisturbed. Techniques and arrangements are proposed to ensure the remainder of the email system continues to function correctly after the insertion of the new gateway logic.