Which tier below is not considered part of the integrated enterprise system architecture?

Name: Which tier below is not considered part of the integrated enterprise system architecture?
Brand: Quizplus
Rating: 4.7 (52 reviews)

Question

Quizplus · Accepted Answer

The firewall tier is not part of the integrated enterprise system architecture. This tier is in place to protect the system from external threats and is designed as a separate layer of security. The other three tiers, user, database, and application, are all part of the integrated enterprise system architecture.

Which Tier Below Is Not Considered Part of the Integrated