Answer:
A domain provides user and group-based security, centralized management of network resources and is physically irrelevant (can be contained in one room or span international borders).
The advantages of Domain model over a workgroup model are:
1. Here ( domain model) we have a centralised administration.
2. Lot of security- which is not there in Workgroup since anyone with the knowledge of credentials of a particular machine can access its resources.
3. lot of scalability
3.lot of extensibility
4. Single sign on