The multiple forest model is a complex implementation process. The cost of implementation is also higher as it requires additional resources (hardware, software, and maintenance). There are several reasons why you might need the multiple forest model:
- Business operations isolations: Businesses can have groups of companies or departments that are required to operate independently. Their dependence on other departments and partner companies may be minimum. In such scenarios, it is good to create a separate forest for them.
- Rapid changes in directory services: Business may have some departments or business units that involve rapid directory changes. For example, R&D, DevOps test environments, and software development departments ...