Trusted authentication with HTTP_HEADER method

HI,

We need to implement trusted authentication with HTTP_HEADER method in XIR2. We are on websphere and AIX(CMS is on AIX) platform and would be using LDAP-AD plugin as we would map active directory users.

1) Can we do a trusted authentication using HTTP_HEADER, LDAP-AD plugin will this combination work?

We would be passing the credentials from our corporate portal to Infoview page which should do the SSO.

2) what is HTTP_Header and how should we use it?

3) We need one more clarification on the user retrieval method, where do we need to implement these methods do we need to implement at the HTTP server level or at application server level?

Please help!!!

Thanks..