[Samba] smb.conf when security = domain

[Eddie]

If samba is configured to be part of a domain (security = domain), are these
following global configuration parameters required/needed?

encrypt passwords
smb passwd file/passdbbackend

I figured out that the "add user script" and "add group script" are needed
to allow samba to create Unix accounts on the fly, but I wasn't sure about
the above parameters

Thanks
Eddie