Gringott's Bank ATM Network Analysis - Essay Example

GRINGOTT'S BANK ATM Overview of the current System Money, it is said, makes the world go round. This has never been truer in context of the global banking industry and financial markets, which are becoming more inter-linked and integrated, creating the need for a new generation of solutions that, operate in real time with impeccable reliability. The current banking system is mainly concentrated on paper transactions and various forms of wire transfers. Any money that needs to be sent is delayed in proportion to the farness of its destination at least in the case of paper transactions. This delays business deals and this delay is also known to have destroyed many lives. When it comes to wire transfers, the most annoying thing in it is with regard to the lengthy and painstaking procedures involved in authentication and also the cost factor is a major concern. The cost of initiating a wire transfer of money say, between America and England would cost a minimum of $15, which is quite costly. Another major factor of concern is the accessibility. Even today, the common man has to go to any branch of a bank even if there are cases where there is only a single branch in most of the cities. Such a limitation makes it difficult for effective and smooth business, when other modern technologies are at hand. The modern era has seen an increase in wireless communication along with the advent of the age of the Internet and the WWW (world wide web). As such, banks today feel the need to take advantage of these developments and modify their current operations in order to incorporate such new technologies and practices. List of Requirements The establishment of any successful ATM network is dependent on the procurement and establishment of the following components: A Department, which operates and looks after the maintenance of the overall ATM infrastructure. A Server at the headquarters for processing all the data. A network of ATM outlets at various locations with the necessary security features. A suitable medium for effective communication among all the requisite devices. Use Case list 1) System Startup: The system is started up when the operator turns the operator switch to the "on" position. The operator will be asked to enter the amount of money currently in the cash dispenser, and a connection to the bank will be established. Then the servicing of customers can begin. 2) System Shutdown: The system is shut down when the operator makes sure that no customer is using the machine, and then turns the operator switch to the "off" position. The connection to the bank will be shut down. Then the operator is free to remove deposited envelopes, replenish cash and paper, etc. 3) Session: A session is started when a customer inserts an ATM card into the card reader slot of the machine. The ATM pulls the card into the machine and reads it. (If the reader cannot read the card due to improper insertion or a damaged stripe, the card is ejected, an error screen is displayed, and the session is aborted.) The customer is asked to enter his/her PIN, and is then allowed to perform one or more transactions, choosing from a menu of possible types of transaction in each case. After each transaction, the customer is asked whether he/she would like to perform another. When the customer is through performing transactions, the card is ejected from the machine and the session ends. If a transaction is aborted due to too many invalid PIN entries, the session is also aborted, with the card being retained in the machine. The customer may abort the session by pressing the Cancel key when entering a PIN or choosing a transaction type. 4) Transaction: A transaction use case is started within a session when the customer chooses a transaction type from a menu of options. The customer will be asked to furnish appropriate details (e.g. account(s) involved, amount). The transaction will then be sent to the bank, along with information from the customer's card and the PIN the customer entered. If the bank approves the transaction, any steps needed to complete the transaction (e.g. dispensing cash or accepting an envelope) will be performed, and then a receipt will be printed. Then the customer will be asked whether he/she wishes to do another transaction. If the bank reports that the customer's PIN is invalid, the Invalid PIN extension will be performed and then an attempt will be made to continue the transaction. If the customer's card is retained due to too many invalid PINs, the transaction will be aborted, and the customer will not be offered the option of doing another. If a transaction is cancelled by the customer, or fails for any reason other than repeated entries of an invalid PIN, a screen will be displayed informing the customer of the reason for the failure of the transaction, and then the customer will be offered the opportunity to do another. The customer may cancel a transaction by pressing the Cancel key as described for each individual type of transaction below. All messages to the bank and responses back are recorded in the ATM's log. 5) Withdrawal Transaction: A withdrawal transaction asks the customer to choose a type of account to withdraw from (e.g. checking) from a menu of possible accounts, and to choose a dollar amount from a menu of possible amounts. The system verifies that it has sufficient money on hand to satisfy the request before sending the transaction to the bank. (If not, the customer is informed and asked to enter a different amount.) If the transaction is approved by the bank, the appropriate amount of cash is dispensed by the machine before it issues a receipt. (The dispensing of cash is also recorded in the ATM's log.) A withdrawal transaction can be cancelled by the customer pressing the Cancel key any time prior to choosing the dollar amount. 6) Deposit Transaction: A deposit transaction asks the customer to choose a type of account to deposit to (e.g. checking) from a menu of possible accounts, and to type in a dollar amount on the keyboard. The transaction is initially sent to the bank to verify that the ATM can accept a deposit from this customer to this account. If the transaction is approved, the machine accepts an envelope from the customer containing cash and/or checks before it issues a receipt. Once the envelope has been received, a second message is sent to the bank, to confirm that the bank can credit the customer's account - contingent on manual verification of the deposit envelope contents by an operator later. (The receipt of an envelope is also recorded in the ATM's log.) A deposit transaction can be cancelled by the customer pressing the Cancel key any time prior to inserting the envelope containing the deposit. The transaction is automatically cancelled if the customer fails to insert the envelope containing the deposit within a reasonable period of time after being asked to do so. 7) Transfer Transaction: A transfer transaction asks the customer to choose a type of account to transfer from (e.g. checking) from a menu of possible accounts, to choose a different account to transfer to, and to type in a dollar amount on the keyboard. No further action is required once the transaction is approved by the bank before printing the receipt. A transfer transaction can be cancelled by the customer pressing the Cancel key any time prior to entering a dollar amount. 8) Inquiry Transaction: An inquiry transaction asks the customer to choose a type of account to inquire about from a menu of possible accounts. No further action is required once the transaction is approved by the bank before printing the receipt. An inquiry transaction can be cancelled by the customer pressing the Cancel key any time prior to choosing the account to inquire about. 9) Invalid PIN Extension: An invalid PIN extension is started from within a transaction when the bank reports that the customer's transaction is disapproved due to an invalid PIN. The customer is required to re-enter the PIN and the original request is sent to the bank again. If the bank now approves the transaction, or disapproves it for some other reason, the original use case is continued; otherwise the process of re-entering the PIN is repeated. Once the PIN is successfully re-entered, it is used for both the current transaction and all subsequent transactions in the session. If the customer fails three times to enter the correct PIN, the card is permanently retained, a screen is displayed informing the customer of this and suggesting he/she contact the bank, and the entire customer session is aborted. If the customer presses Cancel instead of re-entering a PIN, the original transaction is cancelled. Use Case Diagrams The Use case diagram for the ATM is as shown below: CRC Cards: Using CRC cards to assign responsibiities to various classes for the tasks required by the various use cases leads to the creation of the following cards: Class ATM Class CardReader Responsibilities Collaborators Tell ATM when card is inserted ATM Read information from card Card Eject card - Retain card - Class CashDispenser Responsibilities Collaborators Keep track of cash on hand, starting with initial amount - Report whether enough cash is available - Dispense cash - Class CustomerConsole Responsibilities Collaborators Display a message - Display a prompt, accept a PIN from keyboard - Display a prompt and menu, accept a choice from keyboard - Display a prompt, accept a dollar amount from keyboard - Respond to cancel key being pressed by customer - Class EnvelopeAcceptor Responsibilities Collaborators Accept envelope from customer; report if timed out or cancelled Log Class Log Responsibilities Collaborators Log messages sent to bank - Log responses from bank - Log dispensing of cash - Log receiving an envelope - Class NetworkToBank Responsibilities Collaborators Initiate connection to bank at startup - Send message to bank and wait for response Message Log Balances Status Class OperatorPanel Responsibilities Collaborators Inform ATM of changes to state of switch ATM Allow operator to specify amount of initial cash - Class ReceiptPrinter Responsibilities Collaborators Print receipt Receipt Class Session Responsibilities Collaborators Perform session use case ATM CardReader Card CustomerConsole Transaction Update PIN value if customer has to re-enter it - Abstract Class Transaction Responsibilities Collaborators Allow customer to choose a type of transaction ATM CustomerConsole Withdrawal Deposit Transfer Inquiry Perform Transaction Use Case ATM CustomerConsole Withdrawal Deposit Transfer Inquiry Message NetworkToBank Receipt ReceiptPrinter Perform invalid PIN extension CustomerConsole Session CardReader Class Withdrawal Responsibilities Collaborators Perform operations peculiar to withdrawal transaction use case CustomerConsole CashDispenser Message Receipt Class Deposit Responsibilities Collaborators Perform operations peculiar to deposit transaction use case CustomerConsole Message EnvelopeAcceptor Receipt Class Transfer Responsibilities Collaborators Perform operations peculiar to transfer transaction use case CustomerConsole Message Receipt Class Inquiry Responsibilities Collaborators Perform operations peculiar to inquiry transaction use case CustomerConsole Message Receipt Class Balances Responsibilities Collaborators Represent account balance information returned by bank - Class Card Responsibilities Collaborators Represent information encoded on customer's ATM card - Class Message Responsibilities Collaborators Represent information to be sent over network to bank - Class Receipt Responsibilities Collaborators Represent information to be printed on a receipt - Class Status Responsibilities Collaborators Represent transaction status information returned by bank - Class Diagram for Gringott's ATM Shown below is the class diagram for the ATM system. The basic structure of the class diagram arises from the responsibilities and relationships discovered when doing the CRC cards and Interaction Diagrams. (If a class uses another class as a collaborator, or sends a message to an object of that class during an Interaction, then there must either be an association linking objects of those classes, or linking the "sending" class to an object which provides access to an object of the "receiving" class.) In the case of the ATM system, one of the responsibilities of the ATM is to provide access to its component parts for Session and Transaction objects; thus, Session and Transaction have associations to ATM, which in turn has associations to the classes representing the individual component parts. The need for the various classes in the diagram was discovered at various points in the design process. Some classes were discovered when doing analysis Some classes were discovered when doing CRC cards and some classes were discovered when doing detailed design or writing code. Message - used to represent a message to the bank. Receipt - used to encapsulate information to be printed on a receipt. Status - used to represent return value from message to the bank. Balances - used to record balance information returned by the bank. Money - used to represent money amounts, in numerous places. Account Information - contains names of various types of accounts customer can choose from . CLASS DIAGRAM FOR ATM SYSTEM State model for a transaction use case Collaboration (Communication) diagram for one transaction use case Final Evaluation The above diagrams have therefore shown the necessary construction, functioning and architecture of an ATM system. As the diagrams depict, it is indeed an added advantage for Gringott's bank to set up such an ATM chain. The establishment of such a system will result in the establishment of any ATM outlets, which will enhance the market presence of the bank and is sure to increase the customer base of the bank manifold. The cost involved in any kind of banking transactions is slated to reduce with the establishment of the proposed ATM network, which will work wonders by attracting more customers. In addition to this, all such transaction will finish at a very fast rate owing to the high-speed cables that will be used to connect the various terminals of the network. Thus, it can be ascertained that the establishment of the ATM network is a very effective way of decreasing operating costs, reducing transaction times, attracting more customers and reducing the workforce. The last advantage is possible because an ATM centre does not require supervisory staff as it is automated to handle all types of transactions as well as provided with the necessary security features. REFERENCES 1) Doug Rosenberg, Kendall Scott (1999) Applying Use Case Driven Object Modeling With UML. New York: Wiley Eastern. 2) Paul R Reed (1998) Developing Applications With Java and UML. London: Oxford Press. 3) Ram Baugh, Gooch and Jacobson (1997) UML- user guide. Seattle: O'Reilly. 4) Sinan Si Alhir (1997) UML in a Nutshell. London: Wiley Eastern. Read More