Abstract: The integrity of a remote communication unit (14) in a communication system is verified by comparing a hash value generated within the remote unit (14) to a hash value generated within a local unit (24). An interrogation message is generated within an interrogating entity (10) that includes a random seed value, memory range information identifying a memory range within the remote unit that is to be hashed, and position information identifying a position at which the random seed value is to be located within a data stream generated within the remote unit (14). The interrogation message is then delivered to the remote unit (14) which then performs a hashing operation based upon the parameters within the interrogation message to generate a hash value. The hash value is then returned to the interrogating entity (10) for comparison with a control value.

Abstract: Security is provided for an inside network (14) by a security host (26). Connection request messages sent from source hosts (22) in an outside network (12) are intercepted (94) in the security host (26) and prevented from being transmitted on the inside network (14). The user of the source host (22) then establishes a connection (78) to the security host (26) where a dialog session (80, 98, 100) occurs to confirm the user's authenticity and authorization. After the user is confirmed, the intercepted connection request message is released (116) for transmission on the inside network (14) where the intended application service will respond and a communication session will commence.