I have installed BOE on AIX server,
Is it possible to configure AD Authentication on it?
yes you must use the LDAP plugin and configure it against AD. There are SAP notes on it and it's in the XI 3.1 admin guide (as well as some other forum posts). The LDAP plugin is a bit more limiting and doesn't have any built in SSO. For full AD features you must have the CMS on windows and configure AD with kerberos.