1.DB connection is established using APPLSYSPUB user. This user “APPLSYSPUB” is having access to fnd_user view and a small set of other public tables needed to establish the initial connection.
3.Using GUEST/ORACLE password combination and ENCRYPTED_FOUNDATION_PASSWORD string obtained from 2 above, we get Apps schema password.
4.Internally it tries to connect to Apps schema with the password retrieved in step 3 above. If the connection fails, then
a)The GUEST username password is incorrect
b)The FNDNAM (APPS) environment variable is set incorrectly.
c)Some other problem prevented a connection
5 Using Apps password obtained in Step 3 and ENCRYPTED_USER_PASSWORD string from FND_USER table, password for Application user (e.g. SYSADMIN) is obtained.
6. The Application user password obtained in Step 5 is compared to the application user password entered by user in login screen. If both passwords match then user is allowed to get into self-service.
7. A list of responsibilities assigned to that user is shown. The user picks one of the responsibilities listed.
8. Each responsibility has a data group and application defined for it.Together, the data group and application define the Oracle account the responsibility uses.