Take the tour ×  I guess the example can make it easier.  Assume
each Client on a network has an identifier(some alphanumeric
sequence) which identifies it uniquely on the network. Each time
the Client corresponds with the Server over the
network(encrypted), the Client sends its identifier to identify
itself. Now if somehow this identifier is read off the memory of
the device in some way, that device can be impersonated.  Is
there any way this weakness in a system can be done away with?
We sure can force the Client to change its identifier at end of
every session and inform the Server of the new identifier, but
this would again remain stored in memory.  I hope I have managed
to explain in clear enough. Thanks for your time and attention
already.  /////////// Edit /////////// I am strictly looking for
a solution which works in the case of a completely subverted
Client program/OS/environment, which means the attacker can
wilfully hook into any of the system events and processes.
/////////// Edit /////////// I'