CCA Release 2.54
IBM German Bank Pool Institution PIN-Calculation Method
The IBM German Bank Pool Institution PIN calculation method calculates an
institution PIN that is 4 digits in length.
The German Bank Pool Institution PIN-calculation method consists of the following
steps:
1. Encrypt the hexadecimal validation data with an institution key that has a
control vector that specifies the PINGEN (or PINVER) key type to get a 64-bit
quantity.
2. Convert the character format decimalization table to an equivalent array of
sixteen 4-bit hexadecimal digits, and use the decimalization table to convert the
first 6 hexadecimal digits (X'0' to X'F') of the encrypted validation data to
decimal digits (X'0' to X'9'). Call this result newpin.
The digits of newpin are obtained by the following procedure:
For i = 1 to 6 do:
j := encrypted_validation_data(i)
newpin(i) := decimalization_table(j)
end do
3. Select the 4 rightmost digits of newpin. The result is a 4-digit intermediate PIN.
4. If the first digit of the intermediate PIN is 0, assign 1 to the first digit of the
institution PIN, and assign the remaining 3 digits of the intermediate PIN to the
institution PIN.
If the first digit of the intermediate PIN is not 0, assign the value of the
intermediate PIN to the institution PIN.
The PIN is not encrypted.
Example:
Encrypted validation data = E5A4FD67B66AE7C6
Decimalization table index = 123456789ABCDEF
Decimalization table = 12345678912345
Newpin = 45453
Intermediate PIN = 453 (4 rightmost digits of newpin)
Institution PIN = 1453 (first digit is changed to 1
because the intermediate PIN had a
first digit of )
E-6 IBM 4758 CCA Basic Services, Release 2.54, February 2005
