A postal system includes a local computer having a user interface and an
associated storage unit for storing a secure data file that contains
postal (e.g., accounting) data. A secure processing unit interfaces with
the local computer and performs the secure processing normally associated
with a secure postal environment. The secure processing unit can be
designed to receive power from the computer to which it couples, and
generally does not require special interconnect. By using the secure
processing unit to perform the secure processing and the local computer to
perform other postal functions (e.g., user interface), complexity is
reduced which translates to faster speed of operation and a more
economical hardware design.
