If we add noindex to a subdomain, will the traffic to that subdomain still generate domain authority for the primary domain?

[grayloon]

We are trying to decide whether a password protected site, that we will noindex, should be set up as a subdomain or if it should be its own domain. The determining factor here is whether or not having that noindexed subdomain will increase domain authority since its noindexed. Any ideas???

[STPseo]

Not totally sure. You may find it will help the root domain if the sub-domain links back to the root domain and you still let the pages get followed.