Is it possible to establish a trust relationship between two Active Directory domains?

Question

Active Directory

Is it possible somehow to establish a trust relationship between two different Active Directory domains (located on different networks, but connected by routing) without creating a forest so that users of one domain can log in to the server of the second and vice versa?

Answer 1

The concepts Forest and Domain are inseparable; you cannot create a forest without a domain, and vice versa.
Regarding your question:
1. https://technet.microsoft.com/en-us/library/cc7702... (for general development)
2. Depending on the factors, you need to choose the model that suits you: Forest Trusts, External Trusts or Realm (if non-Windows), all this is described in the link from paragraph 1