Chap 11: Analysis and Design

Dave Chaffey, E-Business and E-Commerce Management, 3rd Edition © Marketing Insights Ltd 2007

CHAPTER 11ANALYSIS AND DESIGN

Learning outcomes Summarize approaches for analyzing

requirements for e-business systems Identify key elements of approaches to

improve the interface design and security design of e-commerce systems.

Management issues 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 thee-business?

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 organizations, franchises, supply chains and distribution channels. Along with material and other resource flows, information flows must also be handled effectively in any organization.’

Workflow managementWorkflow 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.

BizFlow

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.

Task analysis and task decomposition Before a process can be designed and

implemented, a more detailed breakdown is required known as ‘task analysis’

Curtis et al. (1992) framework:Level 1 business process are decomposed into:

Level 2 activities which are further divided to:Level 3 tasks and finally:

Level 4 sub-tasks.

Figure 11.1 An example task decomposition for an estate agencySource: Adapted from Chaffey (1998)

Process dependencies

Summarize the order in which activity occur according to the business rules

Data flow diagrams and flow charts are widely used as diagramming techniques Flow process charts Network diagrams Event-driven process chain (EPC) model

Figure 11.2 Symbols used for flow process charts

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

Table 11.5 Elements of the event-driven process chain (EPC) model

Figure 11.4 General model for the EPC process definition model

Data modelling Uses well established techniques used

for relational database design Stages:

1. Identify entities2. Identify attributes of entities3. Identify relationships.

Figure 11.5 Generic B2C ER diagram

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.

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.

Field Attributes of products, example date of birth. Record A collection of fields for one instance of an

entity, example Customer Smith.

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 key 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.

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. 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 fore-business systems the design aim is to maximize the application logic processing including the business rules on the server.

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

The three-tier client server

Require different servers to combine applications logic and database storage

Purpose of each server: Web server. Manages http requests Merchant server. Main location of app. Logic Personalization server. Provides tailored

content Payment commerce server. Manages payment Catalogue server. A document management

server

Figure 11.7 E-business architecture for The B2C Company

User-centred designUnless 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)

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 expertize 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?

Usability

An approach to web-site design intended to enable the completion of user tasks

Involves two key project activities: Expert reviews Usability testing

Four stages of Rosenfeld and Morville (2000)

1. Identify different audiences.2. Rank importance of each to business.3. List the three most important

information needs of audience.4. Ask representatives of each audience

type to develop their own wishlists.

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.

Benefits of personas

Fostering customer centricity Identifies detailed information needs and

steps Test existing web-site design To compare and test the strength and

clarity of communication Can be linked to marketing

Developing a persona

1. Build personal attributes into personas2. Remember that personas are only

models of characteristics and environment

3. Different scenarios can be developed for each persona Info-seeking scenario Purchase scenario

Schneider and Winters (1998) stages in Use Case

1. Identify actors. Actors are typically application users such as customers and employers also other systems

2. Identify use-cases. The sequence of transactions between an actor and a system that support the activities of the actor

3. Relate actors to use-casesSee figure 11.8

4. Develop use-case scenarios See figure 11.9 for a detailed scenario.

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

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

Primary scenario for the Register use-casePre-condition: A user is active on the web site

Scenario: Register

Basic path:

1. Use-case starts when customer presses ‘register’

2. Customer enters name, postal address and email

3. The post/zip code will be checked for validity

4. The customer will select ‘submit’

5. The system will check all fields are present

6. A redirect page will be displayed to thank the customer.

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

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

Designing the information architecture Card sorting

The process of arranging a way of organizing objects on the web site

Blueprints Shows the relationship between pages and

Chap 11: Analysis and Design

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