D-Link DFL-1600 User Manual page 231

21.1. VPN Design Considerations 211
What happens when an employee in possession of a key leaves the
company? If several users are using the same key, it should be
changed of course.
In cases where the key is not directly programmed into a network unit
such as a VPN gateway, how should the key be stored? Should it be
on a floppy? As a pass phrase to memorize? On a smart card? If it is
a physical token, how should it be handled?
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