Heimdal or MIT Kerberos for Windows 3.2.x if Kerberos v5 authentication support is desired. Heimdal is preferred over MIT Kerberos as it will provide OpenAFS the ability to offer enhanced capabilities in future releases. For 64-bit Windows installations, the 64-bit version of Kerberos for Windows is required. For 32-bit Windows installations, the 32-bit version of Kerberos for Windows is required. See 3.2 Kerberos v5 Requirements for additional details.