RocketCalc has developed and maintains a version of OpenSSH that uses Ganglia’s authd authentication. The following is
a is a quote from their web site where the software resides….

Authd is a simple SSL-based authentication mechanism that makes it simple to authenticate users on clusters. Authd was written by Brent N. Chun and is part of the Ganglia package. Authd is used by gexec to launch processes on cluster nodes. We really like gexec and authd. Although gexec is supremely capable for launching jobs, we also thought it would be cool to add authd as an authentication method to OpenSSH. Our patches and source code below do just that. On systems with Ganglia/authd/gexec installed, one can add the modified ssh and use authd for reasonably secure, password-less user authentication on the cluster without any set-up required by the user.