According to some stuffs, the 2-tier architecture has some faults, but following two confuse me:
1) Potential network bottleneck;
2) poor scalability. As the business is tightly coupled with data store.
To 1), I can't understand at all. Why do there exist this problem? In comparison with the 3-tier architecture, here is no any special case when clients connect server, whatever you use 2-tier or 3-tier, the network traffic from client to server is equivalent.
as to 2), it make more confusion to me, in terms of the the book Sun Certified Enterprise Architect Study Guide, here are two ways to improve the scalability of system, first is Vertical, such as increasing CPU and momery, second is horizontal, such as cluster technique.
But, in 2-tier, it can be added CPU or hot backup server to improve performance, so as to achieve the goal of scalability.
Who can give me a sound explanation? I will thanks a lot
best regards
[ April 01, 2005: Message edited by: Along huang ]
[ April 01, 2005: Message edited by: Along huang ]