Talk:Three-tier (computing)

Does the Theory Work?

In a three-tier model, how easily can a web application can be converted to different types of applications?

For example:

Using Jakarta Tomcat <-> Jave 2 Enterprise Edition <-> Mysql

then change it to Apache 2 Web Server <-> PHP <-> Postgre

What type of web application would it be? Well, let's say it is a movie rental web application.

~AT3

Changing the business logic is a pain in the .... Changing PHP for Java Servlets & JSP is very difficult, as the programming is quite diferent. Also, as far as I understand PHP combines both presentation and logic on the same page, whereas a Level 2 JSP implementation implements business logic on servlets and presentation on JSP.

Now regarding the first architecture, it is actually Apache Web Server -> Jakarta Tomcat (Java 2 Enterprise Edition) -> MySQL. The second one is ok. For either of the two, changing for example Apache Web server with MS IIS 4.0 is doable. I have installed IIS with Jakarta. It is also fairly straightfoward to change the database AS LONG AS you use standard ANSI SQL queries.

So basically the theory holds... as long as you don't change the most important part, the business logic. --Threner 03:29, 29 October 2005 (UTC)[reply]

If you use SOA that should take some of the pain away, having all the components at the tiers as stateless independent services that produce and consume SOAP, the theory will work better than, accept you have to go through the pain of making a SOA system.

If you don't the hardest layer to change is generally the business logic, since it can be anything from PHP, ASP, ASP.NET, a Server, JSP, Beans, Cold Fusion, or any number of other custom pieces and will require extensive re-write. If you do the presentation layer correctly that should be easy, and database migraions are not too much of a problem.

Also be warned that my 3-tier system put much of the business logic in the data tier as stored procs. Fun fun fun. Rhooker1236 11:55, 1 September 2006 (UTC)[reply]

Cleanup and merging

For more information on this (and my crazy plans/screw ups) see Talk:Multitier architecture#Cleanup and merging. -- Foofy 07:13, 19 October 2005 (UTC)[reply]

3-Tier is important enough that it deserves its own Wikipedia entry.

Re-merged

I just redid the merge going back the other way, to Three-tier (computing) as the parent, per the apparent consensus in discussion but contrary to the tag direction which I don't think anyone noticed... Georgewilliamherbert 04:39, 26 May 2006 (UTC)[reply]

Comment

I think the merge was needed and was very nice.