System Analysis and Design Week 1 Introduction

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1 System Analysis and Design Week 1 Introduction 1.1 Introduction This is a short session to familiarize understanding some of System Analysis concepts. Here we are going to focus on the following: 1.2 System o System o Key Elements of any System o Analyze ATM System It s a set of detailed methods, procedures and routines established or formulated to carry out certain activity, perform a duty or solve a problem. System Analysis It s the dissection of a system into components then study how those components interact and work. System Analysis and Design Page 1 of 7

2 1) Identifying Problems, Opportunities, and Objectives Activity: Estimating the scope of the project Summarizing the knowledge obtained Documenting the results Output: Feasibility report containing problem definition and summarized objectives. 2) Determining Human Information Requirements Activity: Interviewing user Sampling and investing hard data Questionnaires Observe the decision maker s behavior and environment Prototyping Learn the who, what, where, when, how, and why of the current system Output: Analyst understands how users accomplish their work when interacting with a computer; and begin to know how to make the new system more useful and usable. 3) Analyzing System Needs Activity: Create data flow diagrams. Complete the data dictionary. Analyze the structured decisions made. Prepare and present the system proposal. Output: Present System Proposal and Data Flow Diagram 1.3 Key Elements of any system Any system is a combination of five key elements: People, Hardware, Software, Data, and Telecommunication Networks. System Analysis and Design Page 2 of 7

3 System 1.4 ATM System 1) Identifying Problems, Opportunities, and Objectives Problem: Bank holds accounts for customers and support a service within the bank institution, but there are some customers who can t go to the bank through their working hours. Traditional Transaction So, Opportunities: Objectives Bank issues to design a machine that replace the work of the teller in the bank institution during non-working hours of the bank, using a cash cards authorizing access to account of any customer over the ATM Automated Teller Machine. ATM allows customers to enter their own transactions using cash cards, such as: System Analysis and Design Page 3 of 7

4 Identification The ATM interacts with the customer to gather his transaction information, to the central computer for validation and process, and dispenses cash to the customer. Checking Account type A customer can hold more than one account, at least it can be either checking or savings or/ and both. Validating cash card a bank customer that authorizes access to accounts using an ATM machine has a card, each card contains a bank code and a card number coded in accordance with national standards on credit cards and cash cards to determine the account that the card can access. 2) Determining Human Information Requirements ATM Components System Analysis and Design Page 4 of 7

5 User Characteristics There are several users of the ATM network: Customer: interacts with the ATM network via the ATM, It must be very easy for them to use. Maintainer: maintains the whole system of the ATM, he should be the only person that is allowed to connect a new ATM to the network. ATM Card Requirements: i. Functional requirements are organized concerning two perspectives: A) ATM A.1 Initialize parameters: Maximum withdrawal per day or/and account. Maximum withdrawal per transaction. Minimum cash in the ATM to permit a transaction. Total fund in the ATM at start of day. Input ATM is initialized with total fund is entered. Processing Storing of the parameters Output Parameters are set. A.2 If no cash card is in the ATM, the system should display initial display. System Analysis and Design Page 5 of 7

6 A.3 If the ATM is running out of money no card should be accepted, an error message is displayed. Input A card is entered Processing The amount of cash is less than the total fund. Output Display an error message, and return cash card. A.4 Authorization: starting after the customer has entered his cash card in the ATM. A.5 The ATM has to check if the entered card is a valid cash card. Input Customer enters the cash card. Processing Check if it is a valid cash card, it will be valid if (the information on the card can be read) or (it is not expired) Output Display error message and return cash card if it is invalid. A.6 If the cash card is valid the ATM should read the serial number and bank code. Input Valid cash card Processing Read the serial number Output Initiate authorization dialog. A.7 If a card was entered more than three times in a row at any ATM and the password was wrong each time the card is kept by the ATM. A message will be displayed. Input Enter a wrong password for the fourth time in succession Processing Initiate authorization processresponse from bank computer is to keep the card. Output Display error message that the customer should call the bank. A.8 The kind of transactions the ATM offers is withdrawal. Input Authorization successfully completed Enter the amount to withdraw Processing Amount entered is compared with the account s amount Output Amount of money to be dispensed is displayed, and begin initializing the withdrawal sequence process. A.9 If it is too much withdrawal redo the transaction. Input Customer has entered the amount of money. Processing Error if the amount is greater than the withdrawal per transaction. Output Start transaction or redo, and initiate a transaction dialog if the amount is not within the predefined transaction policy. B) Bank B.1. Authorization (The bank computer gets a request from the ATM to verify an account) B.2. The bank computer checks if the bank code is valid and a bank code is valid if the cash card was issued by the bank. Input Request from the ATM to verify card, serial number and password Processing Check if the cash card was issued by the bank. Output Valid or invalid bank code. System Analysis and Design Page 6 of 7

7 Key Elements Diagram of ATM Database People Hardware Components ATM Bank connection Link Subsystems Controller Customer Bank Technician Entities ATM Activities View their account balance Withdraw cash Deposit funds Accept transaction Reject transactions. Update account details. Feed machine with money. Troubleshoot problems. Print logs Exercise: Design a Key Elements Diagram for a Video Player. System Analysis and Design Page 7 of 7