3-tier architecture -- poor Manageability?

[Seid Myadiyev]

Friends,
Do you agree that the drawback of the 3-tier architecture is Manageability?
Can you please share your knowledge of 1, 2 and 3 – tier architectures and their QoS?
Thank you!
Seid

[Chris Mathews]

3-tier architecture is standard and has a higher level of manageability than say a 4-tier. Before I go off on a tangent I want to make sure we are on the same page.
1-tier Architecture
Tier 1 - Everything
2-tier Architecture
Tier 1 - Client
Tier 2 - Database
3-tier Architecture
Tier 1 - Client (Browser or Application)
Tier 2 - Web and Application (Full J2EE Server)
Tier 3 - Database
4-tier Architecture
Tier 1 - Client (Browser or Application)
Tier 2 - Web (Servlet/JSP Container)
Tier 3 - Application (EJB Container)
Tier 4 - Database
Do these match your definitions for the different tiers?

[Seid Myadiyev]

Chris,
Thank you very much for this, but what are the benefits and drawbacks of each architecture in terms of their Quality of Service (QoS) requirements?
Thanks very much!
Seid

[Thomas Paul]

One huge difference is scalability. Each time you add a tier you are making your application more scaleable because its easier to apply more horsepower to just the tier that needs it.

[Rufus BugleWeed]

I researched this. On the yahoo site or the JR somebody talked about Sun's codecamp. On Sun's site I found a codecamp document. An early chapter was helpful in understanding some of these issues.
I still only scored 66% on common architectures and concepts.
This is a hard area to find data on.