How is it possible for a two-tier client-server architecture to have a fatal flaw? What is the solution to this problem in a multitier client-server architecture?

Client-server designs with two tiers have a fatal flaw. Is a multitier client-server design the answer?

Is there anything really wrong with a two-tier structure? What are the strategies for handling this issue in a client-server architecture with several layers?

.: Consider a chain of processes P₁, P2, ..., Pn implementing a multitiered client-server architecture. Process P; is client of process Pi+1, and P; will return a reply to Pi-1 only after receiving a reply from P+1. What are the main problems with this organization when taking a look at the request-reply perfor- mance at process P₁?