

The state of Washington uses a twelve character identification number system to for its drivers licenses.
 
1) The first five characters are the first five letters of the
individuals surname (last name). If an individuals last name
contains 4 or fewer letters, the symbol * is used to fill in the
remaining spaces.
2) The sixth character is the individuals first initial.
3) The seventh character is the individuals middle initial.
The symbol * is used if an individual does not have a middle
name.
4) The next two characters are obtained by computing
subtracting the individuals year-of-birth (YOB) from 100. In
other words, 100 - YOB.
5) The tenth character is the check digit.
6) The eleventh character is the month-of-birth code. It
assigns a character according to the code presented in the table below.
The alternate codes are used to avoid collisions.

7) The last character is the code for the day of the month on which the individaul was born. The day-of-month-born code is presented in the table below.

 Examples:
| Driver Information |
License Number |
|
|
| Joseph Marshall Pollan |
POLLAJM304PR |
| Born: October 19, 1970 |
|
|
|
| Tracy Holland |
HOLLAT*554J5 |
| Born: April 25, 1945 |
|
|
|
| Alexander William Moe |
MOE**AW240MD |
| Born: July 4, 1976 |
|
The Check Digit Scheme:
Consider the twelve character Washington
State/Manitoba Province
driver's license number a1a2a3a4a5a6a7a8a9a10a11a12.
The check digit a10 is created by first assigning digits to the
non-digit characters in the identification number using the table
below and then performing the following calculation:
a10 = |a1-a2+a3-a4+a5-a6+a7-a8+a9-a11+a12| (mod 10)

This scheme does not catch all single digit errors. It also does
not catch all transposition of adjacent digit errors.
Examples:
A valid number: POLLAJM304PR
Digit Assignments: POLLAJM304PR = 763311430479
Calculation: |a1-a2+a3-a4+a5-a6+a7-a8+a9-a11+a12| (mod 10)
=
|7-6+3-3+1-1+4-3+0-7+9| (mod 10)
= |4|
(mod 10)
= 4 (mod
10)
= 4
Since 4 is the check digit, this is a valid number.
An invalid number: MOE**AZ240MD
Digit Assignments: MOE**AZ247MD = 465001924044
Calculation: |a1-a2+a3-a4+a5-a6+a7-a8+a9-a11+a12| (mod 10)
= |4-6+5-0+0-1+9-2+4-4+4| (mod 10)
= |13| (mod
10)
= 13 (mod 10)
= 3
Since the check digit is 0, not 3, this number is invalid.
Paper Assignment: You are employed by the New York State Department of Motor Vehicles. You have been asked to develop a new drivers' license identification number system for the state. The new identification numbers must encode a person's first and last name, the person's date of birth, and the county in which that person resides. In addition, the identification number must be only ten-characters long, one of
which must be the check digit. Consequently, in addition to creating a hashing function, you also need to develop a check digit scheme for this identification number system.
Write a paper, in the form of a report, that presents the new driver's license identification number systems (with check digit scheme) to the head of the Department of Motor Vehicles. Make a strong case for the adoption of your system by doing the following:
- Give a step-by-step description, with sufficient examples, on how driver's personal information would be used.
- Include a detailed description of the hashing function and the check digit scheme.
- Argue that your system avoids most, if not all, types of collisions, using examples as needed.
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