ABSTRACT
Fixed passwords are no longer appropriate for controlling computer access. Effective access control calls for the use of dynamic passwords, which are generated by tokens, a calculator-type device. Many such devices have now been introduced into the marketplace, but no one is necessarily appropriate for all situations. This chapter discusses the use of dynamic passwords and describes the characteristics of currently available password generators and their advantages and disadvantages in particular situations. A table comparing the features of a selected group of tokens is included.
