Identity Management and SSO

Hi,
I would appreciate if anyone has any information on the below:-

For Web SSO:
1.    What is the difference if we use Web SSO?
2.    Why does Siebel need verification step, is it necessary?
3.    What’s the Security Adapter’s role?, is it necessary?
4.    What is the relation between Siebel Object Manager and Security Adapter?

For Identity Management:
1.    What is the relationship between Application Object Manager and Data Manager?
2.    Need to clarify development procedure.
3.    Is there any other ways Siebel can provide for ID provisioning(ID creation/deletion/suspend/update)?

Regards

Re