decryption mechanism in wpa & wpa2

Dear Sir,

In the decryption in the cell phone number, such as 0958112782

How is the mechanism-09?d?d?d?d?d?d?d?d

1. computing from 00,000,000 to 999,99,999
2. computing from 999,99,999 to 00,000,000
3. computing Randomly

thanks a lot