The best replacement for kerberos is ntlm.

The best alternatives to kerberos are rated as following:
★★★★★  ntlm
★★★★  ldap
★★★  radius
★★★  ssl
★★  ntlm authentication
★  pki
★  nis
★  ssh
★  ntlmv2
★  oauth
★  pam
★  tacacs+
★  cerberus
★  ldap linux
★  ntlm sharepoint 2010
★  ntlm sharepoint 2013
  openid
  gssapi
  x.509
  ntlm v2
  ntlm sharepoint
  sesame
  saml
  gss api
  pgp

Your alternative for kerberos is not listed? Suggest!
Speaking about kerberos, one probably shouldn't forget about ldap.

Other search terms related to kerberos and their ratings are:
★★★★★ ldap
★★★ active directory
★★ hadoop
★ nis
★ openldap
★ keytab file
nfs
You have in mind a companion for kerberos and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of kerberos in all years. Click on graph for more.
kerberos
ntlm
ldap