This document discusses 1-tier, 2-tier, and 3-tier architectures. The 1-tier architecture has all components in one layer, making it simple but insecure. The 2-tier client-server architecture separates the client and database server for better security. The 3-tier architecture introduces a middle layer to move business logic away from the client, improving scalability and security while making the client thinner. Benefits and issues of each architecture are compared, with 3-tier seen as most scalable and secure though also most complex and costly. Sample code demonstrates how the 3 layers of presentation, business logic, and data would communicate in a 3-tier architecture.

2. Disclaimer: This presentation is prepared by trainees of
baabtra as a part of mentoring program. This is not official
document of baabtra –Mentoring Partner
Baabtra-Mentoring Partner is the mentoring division of baabte System Technologies Pvt .
Ltd

3. 3-Tier Architecture

4. 3-Tier Architecture

5. 1-Tier Architecture

6. 1-Tier Architecture
• In 1-Tier Architecture the file you want to work with must be accessible
from a local or shared drive
• This is the simplest of all the architectures, but also the least secure
• Since users have direct access to the files, they could accidentally modify,
delete the file by accident or on purpose
• So 1-tier architecture is simple and cheap, but usually unsecured and data
can easily be lost if you are not careful

7. 2-Tier Architecture

8. 2-Tier Architecture
• This architecture is also called Client-Server architecture because of the
two components
• The client that runs the application and the server that handles the database
back-end
• The client computer usually can’t see the database directly and can only
access the data by starting the client
• This means that the data on the server is much more secure
• Now users are unable to change or delete data unless they have specific
user rights to do so

9. 2-Tier Architecture
• The client-server solution also allows multiple users to access the database
at the same time
• One other huge benefit is that the server is processing data that allows the
client to work on the presentation and business logic only
• This mean that the client and the server is sharing the workload and by
scaling the server to be more powerful than the client
• you are usually able to load many clients to the server allowing more users
to work on the system at the same time.

10. 3-Tier Architecture
• This involves one more layer called the business logic tier, service tier or
middle tier (layer)
• In the client-server solution the client was handling the business logic
and that makes the client “thick”
• A thick client means that it requires heavy traffic with the server, thus
making it difficult to use over slower network connections like Internet and
Wireless
• This means that only little communication is needed between the client and
the middle tier making the client “thin” or “thinner”
• An example of a thin client is an Internet browser that allows you to see
and provide information fast and almost with no delay

11. 3-Tier Architecture
• As more users access the system a three-tier solution is more scalable than
the other solutions because you can add as many middle tiers (running on
each own server) as needed to ensure good performance (N-tier or
multiple-tier).

12. 3-Tier Architecture
• Security is also the best in the three-tier architecture because the middle
layer protects the database tier
• There is one major drawback to the N-tier architecture and that is that the
additional tiers increase the complexity and cost of the installation

13. Differences among 1-Tier,2-Tier,3-Tier Architecture
1-Tier 2-Tier Multi-Tier
Benefits Very simple Good security Exceptional
Inexpensive More scalable security Fastest
No server Faster execution execution
needed “Thin” client
Very scalable
Issues Poor security More costly Very costly
Multi user issues More complex Very complex
“Thick” client
Users Usually 1 (or a 2-100 50-2000 (+)
few)

14. 3-Tier Architecture
from transferobj import tobj UI
from Blogic import Blogic
class gui:
def userip(self):
print 'enter the Airline code'
self.int_Airline_Code=raw_input()
print 'enter the Airline Name'
self.vchr_Airline_Name=raw_input()
print 'enter the Airline Numeric Code'
self.int_Airline_Numeric_Code=raw_input()
tob=tobj()
tob._init_(self.int_Airline_Code,self.vchr_Airline_Name,self.int_Airline_Numeric_Code)
b=Blogic()
b.getdata(tob)

15. 3-Tier Architecture
UI
def main():
g=gui()
g.userip()
main()

16. 3-Tier Architecture
Logic
from transferobj import tobj
from Database2 import Data
class Blogic:
def getdata(self,tob):
self.int_Airline_Code=tob.int_Airline_Code
self.vchr_Airline_Name=tob.vchr_Airline_Name
self.int_Airline_Numeric_Code=tob.int_Airline_Numeric_Code
obj3=Data()
obj3.getdetails(tob)

17. 3-Tier Architecture
DataBase
from transferobj import tobj
import psycopg2
import sys
#Define our connection string
conn_string = " dbname='firstdb'"
# print the connection string we will use to connect
print "Connecting to databasen ->%s" % (conn_string)
# get a connection, if a connect cannot be made an exception will be raised here
conn = psycopg2.connect(conn_string)
# conn.cursor will return a cursor object, you can use this cursor to perform queries
cursor = conn.cursor()
print "Connected!n"

18. 3-Tier Architecture
DataBase
class Data:
def getdetails(self,tob):
self.int_Airline_Code=tob.int_Airline_Code
self.vchr_Airline_Name=tob.vchr_Airline_Name
self.int_Airline_Numeric_Code=tob.int_Airline_Numeric_Code
cursor.execute("insert into tbl_Airlines values(%s,%s,%s)",
(self.int_Airline_Code,self.vchr_Airline_Name,self.int_Airline_Numeric_Code))
cursor.execute("select * from tbl_Airlines");
result=cursor.fetchall()
print result
conn.commit()

21. Reference
http://blog.simcrest.com/what-is-3-tier-architecture-and-why-do-you-need-it
http://www.c-sharpcorner.com/uploadfile/gowth/two-tier-and-three-tier-architecture-
with-example/

22. If this presentation helped you, please visit our
page facebook.com/baabtra and like it.
Thanks in advance.
www.baabtra.com | www.massbaab.com |www.baabte.com

23. Contact Us