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Is it a good practice? RRS feed

  • Question

  • User-2039796023 posted

    The traditional architecture of a 3-tier web application consists data store, web server, and client browser. To use SOA, we added a new service tie in between data store and web server, and each tie is located on physically separated servers. So for a client to reach data, application has to connect through Internet to web server, to intranet service server, and then to the  data store.  In some cases, some service calls service, and then data store.

    Is this the right way to construct a very high traffic web site? 

    Monday, May 10, 2010 9:53 PM

Answers

  • User-952121411 posted

    You should read the following article by Rocky Lhotka.  It directly speaks to some of your concerns about the affect of adding a separate 'physical' tier into the architecture, and the costs and benefits associated with it:

    Should all apps be n-tier?

    http://www.lhotka.net/weblog/ShouldAllAppsBeNtier.aspx

    Read through it as the title doesn't represent all of the information you can extract.

    Thank you,

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Tuesday, May 11, 2010 4:07 PM

All replies

  • User-814327568 posted

    Introducing APP Servers Tier in between your Web Server Tier and Data Tier, would enable you to keep your Web Tier thin and this is good for Very High Traffic Web Application. However by introducing APP Server Tier, we introduce additional delay in retrieving data from data base server. So APP Server needs to be highly optimized for performance by using appropriate techniques like Caching.

    Tuesday, May 11, 2010 12:29 AM
  • User-44086034 posted

     

    Read article on SOA architecture that might answer some of your questions.

     SOA architecture

     

    Tuesday, May 11, 2010 12:58 AM
  • User-2039796023 posted

    Thanks for the link.  

    Tuesday, May 11, 2010 11:17 AM
  • User-2039796023 posted

    I understand Web service has a lot advantages, but performance is not one of them. Adding to the complexity, caching is exactly what we will do next to improve the performance. We can put caching on app server or web server or both. Then the web tier is not thinner.  There is not much benefit left for this architecture.

    Tuesday, May 11, 2010 11:40 AM
  • User-952121411 posted

    You should read the following article by Rocky Lhotka.  It directly speaks to some of your concerns about the affect of adding a separate 'physical' tier into the architecture, and the costs and benefits associated with it:

    Should all apps be n-tier?

    http://www.lhotka.net/weblog/ShouldAllAppsBeNtier.aspx

    Read through it as the title doesn't represent all of the information you can extract.

    Thank you,

    • Marked as answer by Anonymous Thursday, October 7, 2021 12:00 AM
    Tuesday, May 11, 2010 4:07 PM
  • User-2039796023 posted

    Thanks for sharing.

    Rocky Lhotka's article is great. It explained the differences of logical layers and physical tiers of software that many architects ignored. I agree with his conclusions of "Layering is almost always a wonderful thing!" and "tiers should be avoided" for web applications. Basically an n-tier model has (n-1) boundaries, and crossing boundary calls are expensive. It also add complexity in software design.  Only benefit of adding an extra SOA application server tier I can see is it improved overall security. Performance is not a reason to add an extra tier.

     

     

    Wednesday, May 12, 2010 4:02 PM