Multitier architecture

Several terms redirect here. For other uses, see Three-tier system (disambiguation), Tier 1 (disambiguation), Tier 2 (disambiguation), Tier 3 (disambiguation), and Tier 4 (disambiguation).

In software engineering, multitier architecture (often referred to as n-tier architecture) is a client–server architecture in which presentation, application processing and data management functions are physically separated. The most widespread use of multitier architecture is the three-tier architecture (for example, Cisco's Hierarchical internetworking model).

N-tier application architecture provides a model by which developers can create flexible and reusable applications. By segregating an application into tiers, developers acquire the option of modifying or adding a specific tier, instead of reworking the entire application. N-tier architecture is a good fit for small and simple applications because of its simplicity and low-cost. Also, it can be a good starting point when architectural requirements are not clear yet.[1][2] A three-tier architecture is typically composed of a presentation tier, a logic tier, and a data tier.

While the concepts of layer and tier are often used interchangeably, one fairly common point of view is that there is indeed a difference. This view holds that a layer is a logical structuring mechanism for the conceptual elements that make up the software solution, while a tier is a physical structuring mechanism for the hardware elements that make up the system infrastructure.[3][4] For example, a three-layer solution could easily be deployed on a single tier, such in the case of an extreme database-centric architecture called RDBMS-only architecture[5] or in a personal workstation.[6]

  1. ^ Richards, Mark (2020). Fundamentals of Software Architecture: An Engineering Approach (1st ed.). O'Reilly Media. ISBN 978-1492043454.
  2. ^ Richards, Mark (2022). Software Architecture Patterns. O'Reilly Media, Inc. ISBN 9781098134273.
  3. ^ Deployment Patterns (Microsoft Enterprise Architecture, Patterns, and Practices)
  4. ^ Fowler, Martin "Patterns of Enterprise Application Architecture" (2002). Addison Wesley.
  5. ^ Vicente, Alfonso; Etcheverry, Lorena; Sabiguero, Ariel (2021). "An RDBMS-only architecture for web applications". 2021 XLVII Latin American Computing Conference (CLEI). pp. 1–9. doi:10.1109/CLEI53233.2021.9640017. ISBN 978-1-6654-9503-5. S2CID 245387844.
  6. ^ Deployment Patterns (Microsoft Enterprise Architecture, Patterns, and Practices)