Maintain User/Password Authentication for SIP extention account.

Hi,

I'm curious to know , how do you maintain the extension/password for a large user ? The reason i asked, i want that each user maintain their own account and authentication password so can prevent user from abuse their account.

I know that we can export list of user for extension including the password from excel files, but if i want to give the user the ability to reset their own password, i still can't find it. I also see there is possibility to integrate with Active Directory but i still don't see the real implementation howto. (it might be i've no luck, or still can't find my luck ).

Thanks in Advance.
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