N-Tier Architecture Patterns

An N-Tier architecture is a description used to describe the structure of large scale Enterprise Information Systems. These initially grew out older architectural approaches.

  • Monolithic Architecture
  • Client-Server Architecture
  • 3-Tier
    • Thin client
    • Rich client
  • 4-Tier architectures.

The defining characteristic of this progression is a clearly defined interface and/or seperation of responsibility.

The move to being called N-Tier is a reflection of the move to component architectures from

  1. Fundamental Platform Services : Database, Directory Services
  2. Business Domain Tier : Application Server, e.g. J2EE EJB, DCOM or CORBA Service Objects.
  3. Presentation Tier : e.g. Java Servlets/JSP, ASP, PHP.
  4. Client Tier : Thin clients like HTML Pages on Browsers and Rich Clients like Java WebStart & Flash.

In J2ee it is common to divide the Business Domain tier into Data-Access (Entity Beans) & Business Services (Session Beans).

  • In an Entprise SOA (Service Oriented architecture) the ESB would be between tiers 1 & 2.
  • In Mashups you could have the aggregation between tier 3 & 4.

n-tier_architecture_patterns.txt ยท Last modified: 2012/06/14 13:09 by Martin Spamer