3 Tier Architecture in DBMS

August 18, 2019

3 tier architecture in DBMS 

  • DBMS architecture plays a key role in the design, development, implementation, and maintenance of the database management system of the company 
  • All the dynamic web application over the internet uses this three-tier architecture
  • The proper selection of database architecture will solve many design problems initially and also helps in quick and secured data access 
  • Any database management system uses any of the following 2 architectures 
    • 2 tier architecture (two-level)
    • 3 tier architecture (three-level) 
3 tier architecture

3 tier architecture 

  • 3 tier architecture is the most popularly used DBMS architecture 
  •  As the name suggests three tiers it consists of three components in addition with client side and server side application of two-tier architecture, it consists application server layer as an intermediate tier between these two .

Components of 3 tier architecture 

1.Client-side: 

  • It is nothing but the presentation layer (your PC, Tablet, Mobile, etc.) 
  • It sends a request to the server side via the application server layer

2.Application server: 

  • It is present as an intermediate tier between the client and server tires
  • Unlike two-tier architecture, in this requests are not directly send from the client to the server side, when a client sends a request first it is transferred to the application server then this application server  transfers request to the server side, followed by query processing and transaction management
  • This intermediate layer also act as a senses medium for the exchange of partially processed data between server and client

3.Server-side:

  • Nothing but the database of the server side application 
  • It sends responses to the requests received from the client side to the application server and the application server, in turn, transfer them to the client side

Examples of three-tier architecture 

  • All large dynamic web applications  present over the internet or examples of this 3 tier architecture 
  • A large website like prepinsta.com over the internet is the best example, isn’t it?? 

Purpose of three-tier architecture 

  • Integrity: because of the middle layer between client and server side data  corruption can be removed 
  • Security: as there is no direct interaction between client and server we can restrict unauthorized access if any 
  • To provide a clear separation between the user application and physical database
  • Program data independence and multiple views of data 
  • Because of the above features, a large number of users can access a database easily 

Demerits 

  • There might be complexity in implementation and communication 
  • Sometimes it becomes difficult for interaction due to the presence of middle layers and responses may be delayed but they can be easily overcome by efficient server administration