Principles of

Engineering System Design

Dr T Asokan

asok@iitm.ac.in

System Design Examples

Contd..

InSeKTs

Customersupport

Satellite GPSAnd weather

Airways service

Railwayservice

Supplier

User

Server and Data-base

InternetFaxPrinterTelephone

Transmission

Type of User: Visitor/IITM community

User request for directions Request to

Print Map

DestinationDatabase

Electric Power PROVIDE DIRECTIONS AND

OTHER NAVIGATION DETAILS

Acknowledgement that Request was

received

Current Location

Directions from current location to Destination

Printed Map

Maintenance Services

InSeKTs

Service, Tests and Repair

IDEF0 (Integrated Definition for Function Modeling)A0 diagram

A0 DiagramType of User:Visitor/IITMcommunity

User requestfor directions Request to

Print MapDestinationDatabase

Electric Power PROVIDE DIRECTIONSAND OTHER NAVIGATION

DETAILS

Acknowledgement that

Request wasreceivedCurrentLocation

Directions fromcurrent locationto Destination

PrintedMap

MaintenanceServices

InSeKTs

Service, Testsand Repair

Accept Request

Process Request

Search in Database

Find routes

Maintenance

User Request for directions

Power Supply

Acknowledge Request

Display directions

Print Map

InSeKTs

Database

Electricity

Digitized Request

A11 DIAGRAM

AcceptRequest

ProcessRequest

Search inDatabase

Findpossibleroutes

Maintenance

UserRequest fordirections

PowerSupply

Acknowledge Request

Displaydirections

Print Map

InSeKTs

Database

Electricity

Digitized Request

AcceptRequest

ProcessRequest

Search inDatabase

Findpossibleroutes

Maintenance

UserRequest fordirections

PowerSupply

Acknowledge Request

Displaydirections

Print Map

InSeKTs

Database

Electricity

Digitized Request

A111 DIAGRAM

Accept Request

Digitize Request

Database

User requestfor directions

InSeKTs

AcknowledgeRequest

Accept Request

Digitize Request

Database

User requestfor directions

InSeKTs

AcknowledgeRequest

InSeKTs

User Interface Components

Processor

GPS/Navigation aids

Database server

Communication module

Power module

keyboards

Touch screen

Telephone

Speaker

Display Screen

Printer

Fax

Receiver

Transmi-tter

Network components

MORPHOLOGICAL BOX

DISPLAY Telephone Network Printer Directions Database Local Area Network

CRT Monitor Chordless © Airtel Dot Matrix Map andDatabase

©OperationalDatabase

Ring

LCD ©With Chord

Vodaphone Ribbon © Map,DatabaseRoutingAlgorithm

DataWarehouse

Master-Slave or Pipeline

ELD Mobile Idea ©Ink Jet Staffed Controlcenter

Analyticaldatabase

BUS

Gas PlasmaDisplay

Aircel Laser AutomatedControl center

Distributeddatabase

©STAR or SPOKE

© TouchScreen

Reliance Line End-UserDatabase

MESH

TATA ExternaldatabaseHypermediaDatabases

DISPLAY Telephone Network Printer Directions Database Local Area Network

CRT Monitor Chordless © Airtel Dot Matrix Map andDatabase

©OperationalDatabase

Ring

LCD ©With Chord

Vodaphone Ribbon © Map,DatabaseRoutingAlgorithm

DataWarehouse

Master-Slave or Pipeline

ELD Mobile Idea ©Ink Jet Staffed Controlcenter

Analyticaldatabase

BUS

Gas PlasmaDisplay

Aircel Laser AutomatedControl center

Distributeddatabase

©STAR or SPOKE

© TouchScreen

Reliance Line End-UserDatabase

MESH

TATA ExternaldatabaseHypermediaDatabases

REDUNDANCY REQUIREMENTS

Fault detection:•User support/feedback system fails•Access to printer/fax/telephone fails•Power supply system fails•Transmitter fails

Transmitter fails: for satellite GPS - Using hot standby sparing

Transmitter1

error

Transmitter1

error

Transmitter1

error

ControlUnit

mapsSignal from

satellite

User support/feedback system fails: Users maybe accessing from different locations - Using triplicated TMR

Connectinguint1

Connectinguint3

Connectinguint2

Support unit

Support unit

Support unit

User 1

User2

User3

support1

support2

support3

Access to printer/fax/telephone fails - Using cold standby Sparing

Printer1

Printer2

Erroror

Erroror

Control

Unit

Information

Printout

Power supply system fails - Using cold standby Sparing

Power

PowerBackup

Erroror

Erroror

Control

Unit

power signal

Power to system

Weightage allocation for Contact details of IITM residents

InSeKts

Operational Objectives (0.65)

Power cost forDatabase (0.2)

Maintenance Cost(0.2)

Software UpdateCosts (0.3)System protectionupdates (0.2)

Kiosk Security (0.1)

Storage Capacity (0.2)

Number of simultaneousenquires handled (0.05)

Speed of data transfer (0.2)

Speed of the system (0.15)

Security for sensitive data (0.2)

Ease of use (0.2)

Maintenance (0.35)

UDaReS

Unified Data Recording System

SYSTEM DESIGN: Example 3

UDaReS

Unified Data Recording System

1.0 Mission: To develop a unified data-recording system to monitor and control the

academic, administrative and other day-to-day activities across the campus.

2.0 Objectives:

•Online recording and compilation of attendance for students/staff/faculty on a day-to-day basis.•Real time analysis of slot-wise engagement of students/faculty.•Online compilation of student grades and TCF.•Integration with the online database of central library.

• Serve as a real time data base for leave/salary/scholarship computation.

• Monitor usage of various facilities like mess/SFC/ Gym/swimming pool etc. by the students/staff.

• Record faculty/student/staff usage of common services like hospital, engg. unit etc. of the institute and usage of the data for futuristic planning.

• Enable cashless transactions at various campus stores.

• Develop an online database for projects undertaken by IC&SR and provide online access to financial information.

System Context diagram

CampusServices

Faculty/Students/Staff

Library

IC & SR

Gymkhana

Administration

NetworkSystem

StudentFacilities

U-Daresystem

UDRAE Life cycle

DEVELOPMENT PHASE

UDARES LIFE CYCLE

RETIREMENT PHASEASSEMBLING PHASE

REFINEMENT PHASE

MAINTENANCE PHASE

DEPLOYMENT PHASE/OPERATIONAL PHASE

TESTING PHASE

Type of scanners, number ofscanners, method ofcommunication, processingtechniques

Assembling various subsystems,configuring networks, connectingsubsystems to main system

Test the working of varoiussubsystems individually andcollectively to check processparameters

Setting the system towork creatingstudent/staff/faculty records,retrieving records etc.

No of regular checks on the system,Repair time and recuperation time forsystem etc.

No. of updates in the software, scopefor new facilities and addedfunctionalities. No. of days beforesystem requires a status update, No.of new features in the software,Sensitivity refinements of scanners,network refinements etc.

No. of years before thescanners need to be replaced.No. of days before old recordsare revised etc.

3.0 Scope of Project: The project will be limited to: 1. Limited data recording and retrieval by students2. Data recording by all the staff and limited retrieval by authorized staff.3. Unlimited data entry and limited retrieval by faculty.4. Cashless transaction at select establishments/ centres only.

4.0 System Operation Few typical operational scenarios are listed to elaborate on the system functioning.

Scenario 1. Faculty records daily attendance. • An input data device (portable) connected to the network (through cable/wireless) display the options available• Faculty chooses attendance record• System asks for authentication• Faculty provides authentication• System accepts authentication and displays the options available for the faculty• Faculty chooses course name• System display student name and offers opportunity for faculty to enter data.• Faculty enters data and completes the process by logging out.

Updating student attendance on a day-to-day basis

Request to access with portalFeedback for authentication details

Enter authentication detailsFeedback regarding authentication accepted

Request to enter course number

Request to enter date of attendance

Enter the course number

Enter the date of attendance

Feedback regarding course number accepted

Feedback stating details were accepted

Feedback on successful logging out

Display the databaseEnter the attendance details of students

Request to log out of the portal

U-DaresProfessor

Originating Requirements Document (ORD):

Operational Phase1. Input/Output Requirements:

• The system shall accept identification details from professor/students/staff.• The system shall give feedback to user within x seconds.• The system shall display fonts at least to the size of ‘y’• The system shall have provision to enter fees payment details by the bank personnel

• The system shall have provision for auto generating mail for request of slot exchange with other faculty • The system shall have provision to send mail to students notifying them regarding scholarships etc. •The system shall compile the staff attendance data•The system shall send mail to the students regarding changes in the class schedules

Technology/ System wide requirements:

• The system shall auto-save data every 30 seconds •The system shall allocate 1Gb space for every faculty, 500Mb space for every student/staff

• The system shall have a processing speed of 5GHz or more•The system shall use Ipv6 protocol for networking

Use U-Dare Services

RequestU dare Services

Students

Software regulations

Com-puters

Maintenance system

Provide support

Provide U- Dare Services

Main server

Maintenance personnelStaff Faculty

EXTERNAL SYSTEM DIAGRAM

Request for desireddata service

Seminar info

ask for info

Provide info

Request forservice,input,password,course-id etc.

Provide service

Use service

feedback give required info

Faculty/staff/students DHU Server Adblock

Anamoly check

Monitor operations Software/hardwarecheck

Maintenance Housing

Keep check onfunctioning ofsystem

a.c.,support etc

Display seminar

EXTERNAL SYSTEM DIAGRAMDisplay Unit

A-0 Context diagram

Provide U-DARESServices

Username/ password

Attendance details

Grade/scholarship info

Lit-soc event schedule

Slot wise listing

A0

Request slot exchange/extra hour

Updated attendance database

Mail request for slot exchange

Scholarship allotment and renewal

Updated Lit-Soc allotment database

Recorded staff attendance

Fees database

User Identity Authentication A1

Accept User Request A2

Provide Services A3

User Identity Authentication A4

Maintain Services A5

User Identity Authentication A1

Request

Provide Services

User Identity Authentication A4

Maintain Services A5

A0 diagram:

Data searchrequest

User IdentityAuthentication

(A1) Accept user request/provid

e feedback (A2)

Control operation (A3)

Provide utility services (A4)

Maintenance and repair (A5)

Feedback

Display data

Provide navigation services

Proper functioning

Enable cashless transaction

UDARE SYSTEM

Network database Power supply

Navigationrequest

Cashless transaction

request

Maintenance services

Data searchrequest

User IdentityAuthentication

(A1) Accept user request/provid

e feedback (A2)

Control operation (A3)

Provide utility services (A4)

Maintenance and repair (A5)

Feedback

Display data

Provide navigation services

Proper functioning

Enable cashless transaction

UDARE SYSTEM

Network database Power supply

Navigationrequest

Cashless transaction

request

Maintenance services

A3 diagram:

Data searchrequest

Processrequest (A31)

Search for data (A32)

Extract data (A33)

Feedback

Provide navigation details

Display information

Network database Power supply

Navigationrequest

Cashless transaction

request

Data searchrequest

Processrequest (A31)

Search for data (A32)

Extract data (A33)

Feedback

Provide navigation details

Display information

Network database Power supply

Navigationrequest

Cashless transaction

request

UDARETransaction details

A32 diagram:

Network database

Power supply

Connect to the network (A321)

Login and password

Search for desired data in the network database (A322)

Extract data from the network

UDARE

Network database

Power supply

Connect to the network (A321)

Login and password

Search for desired data in the network database (A322)

Extract data from the network

UDARE

A322 diagram

Network database

Power supply

Find the category of the information

asked by the user

A3321

Connect to the network Collect data from

the corresponding category (academic/ administrative/ general) A332

Extract data

UDARE

Network database

Power supply

Find the category of the information

asked by the user

A3321

Connect to the network Collect data from

the corresponding category (academic/ administrative/ general) A332

Extract data

UDARE

A11

PROVIDE U-DARE SERVICE

User identityAuthentication

Accept user request/ provide

feed back

Controloperation

Provide services Maintenance and repair

Process request Search data Extract data

Connect to network Search for data in database

Find the category of infunction asked by

user

Collect data

Lower-levelfunction

A31211 A31212 A31213 A31221 A31222 A31223

A3122A3121

A3211 A3212 A3213…

A321

A331Level-3 function

A332A311 A312

A31 A33A32

A12…A21 A22 A23

A1 A2A3 A4 A5

Level-2 function

Level-1 function

A41 A42 A43…. A51 A52 A53…

A322

A11

PROVIDE U-DARE SERVICE

User identityAuthentication

Accept user request/ provide

feed back

Controloperation

Provide services Maintenance and repair

Process request Search data Extract data

Connect to network Search for data in database

Find the category of infunction asked by

user

Collect data

Lower-levelfunction

A31211 A31212 A31213 A31221 A31222 A31223

A3122A3121

A3211 A3212 A3213…

A321

A331Level-3 function

A332A311 A312

A31 A33A32

A12…A21 A22 A23

A1 A2A3 A4 A5

Level-2 function

Level-1 function

A41 A42 A43…. A51 A52 A53…

A322

PROVIDE U-DARE SERVICE

User identityAuthentication

Accept user request/ provide

feed back

Controloperation

Provide services Maintenance and repair

Process request Search data Extract data

Connect to network Search for data in database

Find the category of infunction asked by

user

Collect data

Lower-levelfunction

A31211 A31212 A31213 A31221 A31222 A31223

A3122A3121

A3211 A3212 A3213…

A321

A331Level-3 function

A332A311 A312

A31 A33A32

A12…A21 A22 A23

A1 A2A3 A4 A5

Level-2 function

Level-1 function

A41 A42 A43…. A51 A52 A53…

A322

UDARE System

DATA gathering(0.3)

Speed ofprocess(0.2)

Accuracy ofdata gathered(0.5)

Maintenanceof gatheringdevices(0.3)

Compilation,updatingof data(0.3)

Speed ofprocess(0.3)

Consistency ofcompiling andupdating(0.7)

Displaying/providingdata tousers(0.2)

Featuresshown(0.5)

privacy ofusers’data(0.2)

Users’ease ofusing/displaying(0.3)

Additionalfeatures(0.1)

Facility tosearch(0.3)

Availability/accessibility ofextra features(0.7)

Maintenancesecurity(0.1)

Maintenancecost(0.5)

Updating ofsecuritysystem(0.3)

Powerconsumptionin theprocess

Morphological Boxes:

Plastic Polymer

Metal FRP

Vinyl Coated Paper

Bluetooth LAN

Wi-Fi Wi-Max

Password

Iris eader

Fingerprint scan

Photo-verify

Voice recognition

Morphological box:

Informationexchange

processingcomponent

Nodes Networkarchitecturecomponent

Informationdisplayingcomponent

Informationenteringcomponent

Informationprocessingcomponent

Errordetectioncomponent

Errorcorrectioncomponent

Threatcorrectioncomponent

Threatdetectioncomponent

SQLserver16 bit

SQLserver32 bit

5 GHz

10 GHz

250

400

Nodebranching=5

Nodebranching=10

15.4”CRTscreen

17”LCDscreen

64characterkeypad

Symantectouchpad

2 GHz

1.66 GHz

Even paritycheckdetector

Even paritycorrector

Odd paritycorrector

Odd paritycheckdetector

Customizableanti-virus

virus scan

firewall

Interface Design

Interface requirements: Transfer of data between different modules.

Operational concept: Intranet (LAN based system).

DHUs---------------Server--------------Display unitSystem shall have shared memory network with storage at server.

Interface options

• wi-fi• Using LAN cables• Telephone connection• Wi-fi is too expensive. Data transfer is slow.• Telephone connection is slow. • LAN cables are already present in almost all the rooms. Fast and cheap.•Select LAN

Integration and qualification

Supplemental topics

• Graphical modelling techniques• Decision analysis for design tradeoffs• Uncertainty in decision making• System reliability • Statistical tools for system design

THANK YOU