NFS with user credentials

Hello,

I am creating NFS sharing and would like to add user credentials in there.  

However, it looks like NFSv4 can do but it require kerberos.   Searching some material it looks I need to setup another KDC like using FreeIPA.  Rather then setup within FreeNAS itself.

Could you please advise what is the move simple way for NFS sharing with user credentials?

Thanks!