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Chapter 11 Analysis and Design

Chapter 11 Analysis and Design. Learning objectives. Summarize approaches for analysing requirements for e-business systems Identify key elements of approaches to improve the interface design and security design of e-commerce systems . Issues for managers.

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Chapter 11 Analysis and Design

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  1. Chapter 11Analysis and Design

  2. Learning objectives • Summarize approaches for analysing requirements for e-business systems • Identify key elements of approaches to improve the interface design and security design of e-commerce systems

  3. Issues for managers • What are the critical success factors for analysis and design of e-business systems? • What is the balance between requirements for usable and secure systems and the costs of designing them in this manner? • What are the best approaches for incorporating new IS solutions with legacy systems into the architectural design of the e-business?

  4. Analysis for e-business • Understanding processes and information flows to improve service delivery • Pant and Ravichandran (2001) say:‘Information is an agent of coordination and control and serves as a glue that holds together organisations, franchises, supply chains and distribution channels. Along with material and other resource flows, information flows must also be handled effectively in any organisation.’

  5. Workflow management Workflow is ‘the automation of a business process, in whole or part during which documents, information or tasks are passed from one participant to another for action, according to a set of procedural rules.’ Examples: • Booking a holiday • Handling a customer complaint • Receiving a customer order

  6. Process modelling • Often use a hierarchical method of establishing • the processes and their constituent sub-processes • the dependencies between processes • the inputs (resources) needed by the processes and the outputs • Complete activity 11.2 using Figure 11.2 and Table 11.2 for how to improve processes

  7. An example task decomposition for an estate agency Figure 11.1 An example task decomposition for an estate agency Source: Chaffey (1998)

  8. Symbols used for flow process charts Figure 11.2 Symbols used for flow process charts

  9. Flow process chart showing the main operations performed by users when working using workflow software Figure 11.3Flow process chart showing the main operations performed by users when working using workflow software

  10. Data modelling • Uses well established techniques used for relational database design • Stages: • Identify entities • Identify attributes of entities • Identify relationships

  11. 1. Identify entities • Entities define the broad groupings of information such as information about different people, transactions or products. Examples include customer, employee, sales orders, purchase orders. When the design is implemented each design will form a database table. • Entity A grouping of related data, example customer entity. Implementation as table. • Database table Each database comprises several tables.

  12. 2 Identify attributes • Entities have different properties known as attributes that describe the characteristics of any single instance of an entity. For example, the customer entity has attributes such as name, phone number and e-mail address. When the design is implemented each attribute will form a field, and the collection of fields for one instance of the entity such as a particular customer will form a record. • Attribute A property or characteristic of an entity, implementation as field. • K Field Attributes of products, example date of birth. • L Record A collection of fields for one instance of an entity, example Customer Smith.

  13. 3 Identify relationships • The relationships between entities requires identification of which fields are used to link the tables. For example, for each order a customer places we need to know which customer has placed the order and which product they have ordered. As is evident from Figure 11.5, the fields customer id and product id are used to relate the order information between the three tables. The fields that are used to relate tables are referred to as key fields. A primary is used to uniquely identify each instance of an entity and a secondary key is used to link to a primary key in another table. • Relationship Describes how different tables are linked. • Primary key The field that uniquely identifies each record in a table. • Secondary key A field that is used to link tables, by linking to a primary key in another table.

  14. Generic B2C ER diagram Figure 11.5 Generic B2C ER diagram

  15. Client / server architecture – separation of functions • Data storage. Predominantly on server. Client storage is ideally limited to cookies for identification of users and session tracking. Cookie identifiers for each system user are then related to the data for the user which is stored on a database server. • Query processing. Predominntly on the server, although some validation can be performed on the client. • Display. This is largely a client function. • Application logic. Traditionally, in early PC applications this has been a client function, but for e-business systems the design aim is to maximize the application logic processing including the business rules on the server.

  16. Three-tier client server in an e-business environment Figure 11.6 Three-tier client server in an e-business environment

  17. E-business architecture for the B2C company Figure 11.7 E-business architecture for The B2C Company

  18. User centred design ‘Unless a web site meets the needs of the intended users it will not meet the needs of the organization providing the web site. Web site development should be user-centred, evaluating the evolving design against user requirements.’ (Bevan, 1999a)

  19. Analysis considerations (Bevan) • Who are the important users? • What is their purpose for accessing the site? • How frequently will they visit the site? • What experience and expertise do they have? • What nationality are they? Can they read English? • What type of information are they looking for? • How will they want to use the information: read it on the screen, print it or download it? • What type of browsers will they use? How fast will their communication links be? • How large a screen/window will they use, with how many colours?

  20. 4 stages of Rosenfeld and Morville (1998) • Identify different audiences. • Rank importance of each to business. • List the three most important information needs of audience. • Ask representatives of each audience type to develop their own wishlists.

  21. Use-case analysis • The use-case method of process analysis and modelling was developed in the early 1990s as part of the development of object-oriented techniques. It is part of a methodology known as Unified Modelling Language (UML) that attempts to unify the approaches that preceded it such as the Booch, OMT and Objectory notations. • Use-case modelling A user-centred approach to modelling system requirements. • Unified Modelling Language (UML) A language used to specify, visualize and document the artefacts of an object-oriented system.

  22. Schneider and Winters (1998) stages in Use Case • Identify actors. Actors are typically application users such as customers and employers also other systems. • Identify use-cases. The sequence of transactions between an actor and a system that support the activities of the actor. • Relate actors to use-cases. See Figure 11.8. • Develop use-case scenarios. See Figure 11.9 for a detailed scenario.

  23. Relationship between actors and use-cases for the B2C Company, sell-side e-commerce site Figure 11.8 Relationship between actors and use-cases for The B2C Company, sell-side e-commerce site

  24. Primary use case scenario for an entire e-commerce purchase cycle Figure 11.9 Primary use-case scenario for an entire e-commerce purchase cycle

  25. Primary scenario for the Register use-cases for the B2C Company Figure 11.10 Primary scenario for the Register use-cases for The B2C Company

  26. Clear user scenario options at the RS Components site (www.rswww.com) Figure 11.11 Clear user scenario options at the RS Components site (www.rswww.com)

  27. Customer orientation • ‘Web users are notoriously fickle: • They take one look at a home page and leave after a few seconds if they can't figure it out. • The abundance of choice and the ease of going elsewhere puts a huge premium on making it extremely easy to enter a site.’ Nielsen www.useit.com

  28. I want to... I want to... I want to... I want to... Customer scenarios and service quality • A customer scenario is a set of tasks that a particular customer wants or needs to do in order to accomplish his or her desired outcome. Patricia Seybold, The Customer Revolution Successful Outcome: Customer • Example: • New customer – open online account • Existing customer – transfer account online • Existing customer – find additional product

  29. Site design issues • Style and personality + design • Support the brand • Site organisation • Fits audience’s information needs • Site navigation • Clear, simple, consistent • Page design • Clear, simple, consistent • Content • Engaging and relevant Covered by the eight principles that follow

  30. Site design principle 1 Standards ‘Users spend most of their time on other sites. This means that users prefer your site to work the same way as all the other sites they already know… Think Yahoo and Amazon. Think "shopping cart" and the silly little icon. Think blue text links’. Jakob Nielsen - www.useit.com

  31. Principle 2 Support marketing objectives • Support customer lifecycle • Acquisition – of new or existing customers • Retention – gain repeat visitors • Extension - cross- and up-selling • Support communications objectives • 3 key tactics • Communicate the online value proposition • Establish credibility • Convert customer to action

  32. Principle 3 Customer orientation • Content + services support a range of audiences and… • Different segments • 4 familiarities – With Internet – With company – With products – With web site

  33. Principle 4 Lowest Common Denominator • Access speed • Screen resolution and colour depth • Web browser type • Browser configuration • Text size • Plug-ins www.usability.serco.com

  34. Principle 5 Aesthetics fit the brand Aesthetics = Graphics + Colour + Style + Layout + Typography • Site personality • How would you describe the site if it were a person? E.g. Formal, Fun, Engaging, Entertaining, Professional • Site style • Information vs graphics intensive • Cluttered vs clean • Are personality and style consistent with brand and customer orientation?

  35. (a) (b) (c) (d) Back DTI Cisco Principle 6 Get the structure right

  36. Principle 7 Make navigation easy According to Nielsen, need to establish: • Where am I? • Where have I been? • Where do I want to go? Context. Consistency. Simplicity.Use accepted standards for navigation:

  37. ‘Go with the flow’ Visitor in control An enjoyable experience ‘Think like a client’ Navigation continued Enter by: • user need • product / service • audience type • search To: • alternate home pages

  38. Principle 8 Support user psychology Hofacker’s 5 stages of information processing • Exposure – can it be seen? • Attention – does it grab? • Comprehension and perception - is message understood? • Yielding and acceptance : Is it credible and believable? • Retention – is the message and experience remembered?

  39. Different types of audience for the web site of the B2B Company Figure 11.12Different types of audience for the web site of The B2B Company

  40. Different stages of user familiarity with the Internet Figure 11.13Different stages of user familiarity with the Internet Source: The Netpoll Internet Usage curve, www.netpoll.net

  41. A personality that appeals to a broad audience at Egg.com

  42. (a) Narrow and deep and (b) Broad and shallow organization schemes Figure 11.15 (a) Narrow and deep and (b) broad and shallow organization schemes

  43. Broad and shallow organization scheme for consumers at Sainsburys to You Site Figure 11.16Broad and shallow organization scheme for consumers at Sainsbury’s to You Site (www.sainsburystoyou.co.uk) reproduced by kind permission of Sainsbury’s Supermarkets Ltd

  44. Broad organization schemes and professional style at Cisco.com Figure 11.17 Broad organization schemes and professional style at Cisco.com

  45. Security eggxample • On 24 August 2000, The Financial Times reported how a criminal gang used bogus identities to obtain credit cards and loans from online bank Egg. The bank was defrauded of approximately £10,000 through multiple applications for online banking. Once the cards and loans were granted, with spending limits of up to £2000, the gang used them to make thousands of pounds of purchases, both online and in shops. Bank spokesmen said the crime represented no threat to the bank’s customers, but fraud is still a risk to the banks. The spokesman was also keen to point out that fraudulent applications for credit existed long before the Internet.

  46. Parties involved in secure transactions • Purchasers. These are the consumers buying the goods. • Merchants. These are the retailers. • Certification Authority (CA). This is a body that issues digital certificates that confirm the identity of purchasers and merchants. • Banks. These are traditional banks. • Electronic token issuer. A virtual bank that issues digital currency.

  47. Main security risks • (a) Transaction or credit card details stolen in transit. • (b) Customer’s credit card details stolen from merchant’s server. • (c) Merchant or customer is not who they claim to be.

  48. Security requirements for e-commerce • Authentication – are parties to the transaction who they claim to be? • Privacy and confidentiality – is transaction data protected? The consumer may want to make an anonymous purchase. Are all non-essential traces of a transaction removed from the public network and all intermediary records eliminated? • Integrity – checks that the message sent is complete i.e. that it isn’t corrupted. • Non-repudiability – ensures sender cannot deny sending message. • Availability – how can threats to the continuity and performance of the system be eliminated?

  49. Public-key or asymmetric encryption Figure 11.18 Public-key or asymmetric encryption

  50. SET Figure 11.19 An example of the Secure Electronic Transaction (SET) standard

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