Dell (Quest) Authentication Services can be integrated with MongoDB Enterprise starting from version 2.6, allowing for LDAP and Kerberos authentication. The integration process involves three steps: configuring the hostname and DNS resolution, installing MongoDB Enterprise, and setting up Quest Authentication Services. Once set up, MongoDB can use Quest's PAM module to authenticate LDAP users and the QAS "vasd" daemon manages communications with Active Directory. Additionally, MongoDB can be configured for Kerberos authentication using Quest Authentication Services, which involves creating a user in Active Directory with an SPN for the mongodb service and configuring the MIT Kerberos configuration file. With this integration, organizations deploying Quest Authentication Services can integrate their MongoDB Enterprise systems into their existing security infrastructure without additional operational overhead.