Fwd: How to configure RADIUS +LDAP using SASL/Certificate based binding instead of usernames and passwords

Hi, I am working on RADIUS with LDAP as backend for authenticating users. I configured rlm_ldap on RADIUS server with username and plaintext password and I am able to authenticate RADIUS client using LDAP. But I want to configure RADIUS server with certificates instead of using usernames and passwords. Please guide me how to achieve this,is there any help/doc how to configure LDAP SASL bind for RADIUS Server. Waiting for your inputs. Thanks and Regards, Pramod