Security check method and apparatus reduces problmes that can arise if the
user security data set becomes known by unauthorized persons. To address this problem
only part of the user data set is recorded in insecure sections of the system.
For example, a security check preventing unauthorized remote access to a shared
computer is provided by capturing a user data set representing a user's iris, operating
the user's personal computer to select only a portion of the captured data set
requested by the shared computer and transmitting the portion along a telecommunications
line. The shared computer derives partial data sets from stored user data sets
using a similar selection to that used by personal computer and compares the partial
data set it has derived with the partial data set transmitted by the personal computer
in deciding whether to grant access. Point-of-sale devices and cards recording
only partial user data sets are also disclosed.
