The basic version of Search Guard provides TLS/SSL encrypted intra-cluster communication and also HTTP basic authentication totally free of charge also for comm

The basic version of Search Guard provides TLS/SSL encrypted intra-cluster communication and also HTTP basic authentication totally free of charge also for commercial projects. Only for authentication methods like LDAP or Kerberos, or for advanced features like Document-Level-Security and audit logging a license is needed. Disclaimer: I work for floragunn/Search Guard.