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Electronic Commerce MIS 4108. Session 7: Designing, Building and Evaluating Web Sites. Session Objectives. The objectives of this session are: To analyse some basic Web site design principles To construct a Web site using e-commerce and Web-based software
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Electronic CommerceMIS 4108 Session 7: Designing, Building and Evaluating Web Sites
Session Objectives • The objectives of this session are: • To analyse some basic Web site design principles • To construct a Web site using e-commerce and Web-based software • To apply five criteria in order to determine the credibility of an Internet source • To test the usability of Web sites Designing, Building and Evaluating Web Sites
Web Site Design Principles1,2 • In this section we will: • Briefly discuss interface design • Present some Web site design principles http://www.cybermarket.co.uk/ishop/images/923/429_904.jpg Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • What is an interface? • It is the front end (or user controls) of a device • E.g. a remote control is the interface for a television set • Or a light switch is the interface for an electric light Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • So what makes a good Web interface? • It must be easy to use • The Web site functionality must be easy to deduce • Important items are always available, yet not intrusive • E-commerce site should provide links to the checkout • The purpose of the Web site must be immediately understandable; things must be arranged logically • This includes no cryptic icons • In addition, the site should be interesting and colourful (without being irritating) Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • When designing a Web site the designer must consider: • The type of screen or device that the Web page will be displayed on (is it in colour etc.) • Whether the page will be printed • Although this is a secondary issue • The size of the screen • The designer unfortunately does not have full control over these media Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • It is important to set a Web site theme. This is a multi-step process: • Set the Web site goals • Determine your audience • Define the look and feel of the Web site Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • To determine the goals of your Web site consider asking the following questions: • What is the purpose of creating your Web site? • Should I concentrate on only one goal? • What will happen if the goals change and how will it affect the maintenance of the Web site? • Goals need to be balanced against available resources and time Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • To determine the audience of the Web site consider the following factors: • Visitor’s age: young, elderly or ageless? • Language: is there a requirement to support more than one? • Culture • Income group: who can afford your product/service? • Educational sophistication: scientific Web sites have less images • Attention span: after a few clicks the visitor might leave Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • When considering the Web site look and feel it is important to communicate: • The company’s logos, name, products and location • The unique qualities of the company Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Design principles • Nonlinear presentation • One or two screens per page • Simple navigation • Small graphics for faster page loading • Appealing visual effects Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • The WWW is characterised by: • Non-linear information delivery • Pages that are viewed on desktop PCs, Notebooks computers, Web-enabled mobile phones and Palm PCs • Multiple Internet connection options including Fibre optic lines, TV cable and dial-up phone lines • These characteristics must be considered when designing a Web site Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Nonlinear Presentation: • Traditional media, e.g. a lecture, present information in a linear way • A Web site should utilise multi-dimensional hyperlinks for quick, user-centered navigation Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • One or Two Screens Per Page: • The home page of a Web site should be no longer than one or two pages • Effective home pages present corporate information, logos and links on the first or second screen • This prevents the need for a significant amount of scrolling, since the top of the page is what a visitor sees when entering the site Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Simple Navigation: • The layout of a Web site should be clear and simple allowing easy navigation • Hyperlinks should be grouped together logically • Each hyperlink should connect a major topic or category e.g. Products Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Navigational links could be presented as: • A bar of file folders • A line of small rectangular or oval buttons • A list of underlined text • For easy navigation links should be placed: • On the left, right or top side of the screen • Or frames could be used which freeze the navigation controls on the screen Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Smaller Graphics For Faster Page Loading: • The larger the graphics the longer a Web page will take to load, especially on a narrow-band connection (e.g. dial-up) • Visitors will probably get fed up and leave the site Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • As a general rule: • JPEG (Joint Photographic Expert Group image format) is a 24-bit (16.7 million colours) image format • Photographs should use the JPEG format • A JPEG pictures on a Web page should be smaller than 50KB • Not more than two (2) 50KB JPEG images should be on a single Web Page Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Alternatively: • The GIF format (Graphics Interchange Format by CompuServe) is an 8-bit (256 colours) image format • The GIF format is therefore suitable for navigation buttons, logos and Icons • Navigation buttons should be smaller than 5KB each • Typical buttons are 1-2KB each Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Appealing Visual Effects: • Appealing visual effect can be made using the right combination of style, layout and colour • 12 point Times New Roman or 11 point Arial fonts are typically used for regular text • Headings are usually in a different colour, bold or in a larger font Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Colour contrast between text and background is crucial • It is best to use a light background colour and dark text • Special effect (e,g. blinking text) are suitable for short text strings, e,g, “Special Offer” not long sentences • Always check the page layout on 12.1” – 15” diagonal screens since this is the monitor size for the average user Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Some additional design hints include: • Always ensure that the user can get to all important pages (e.g. product descriptions) using a small number of mouse clicks • Users get fed-up after a few mouse clicks • Always design your Web site for the slowest connection speed, and the earliest browser used by your target audience Designing, Building and Evaluating Web Sites
Web Site Design Principles Cont’d • Some additional design hints include: • When creating information sites include a lot of white space; make the pages simple and uncluttered • Users get fed-up after a few mouse clicks • Always write an outline for your content and decide whether each major topic will be on a separate Web page (recommended); and which sub-topics require their own pages Designing, Building and Evaluating Web Sites
Constructing a Web Site • Software requirements • Hardware requirements Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d • From the company goals you should be able to estimate • The number of visitors that will use your site • The number of pages viewed by the average visitor • The average and maximum allowed size of each page • The maximum allowed number of simultaneous visitors • This allows the software and hardware requirements to be determined Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d • First let us review some fundamentals about Web clients and servers Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Clients and Servers • When an individual connects to the Internet to view a document, they become a client on the Webs client/server network • The client/server architecture is used for LANs, WANs and the Web. • Typical request serviced by servers connected to these networks include request to print, to retrieve information and to access databases Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Clients and Servers • Web servers typically have • More memory • Larger and faster disk drives than client computers • Web browser software e.g. IE, Netscape and Firefox is the software that makes computers work as Web clients • The Internet connects several different types of computers together, therefore Web software must be platform neutral Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Dynamic Content • A static page is an unchanging page retrieved from a disk • A dynamic page is a page created by a program (script) based on user input • E.g. a Web client inquires about the status of an order and the Web page that is returned is created from information stored in a database • This property (being dynamic) can affect the performance of the Web Server • static pages are delivered faster than dynamic pages Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Dynamic Content • The first Web site to provide dynamic pages used server side scripting • Programs running on the Web server that create web pages • These technologies are slow • Newer technologies used for generating dynamic content include: • Microsoft’s Active Server pages (ASP) • Sun’s Java Server Pages (JSP) • Apache’s PHP Hypertext Preprocessor (PHP) Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Dynamic Web Pages: The Future • Some critics say that ASP/JSP/PHP etc. do not solve the problem since they simply shift the responsibility of Web page creation from people to programs • A project that is currently underway to tackle the problem of dynamic Web page creation is the Apache Cocoon project Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Dynamic Web Pages: The Future • The Apache Cocoon project: • Is creating a Web development framework that • Allows programmers to query the system using data in XML format • Receives output in multiple formats including HTML • The content is stored in XML tags which describes the semantics (meaning) of each content item • A Java servlet handles the information request • A style sheet is applied to the data Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Servers • A Server is any computer used to provide files or make applications available to other computers connected to it through a network • Server software refers to the programs that run on the server • Web Servers are connected to the Internet and serve Web pages (e.g. Apache) Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Servers • E-mail Servers handle incoming and outgoing email • Database Servers are server computers on which database management software runs Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Client/Server Communication • When a Web Client requests a page from a Web server the following occurs • The request is converted into HTTP by the browser and sent to the Web Server • The Server receives the request and retrieves the information requested by the Client • The Server formats the information using HTTP and sends it back to the Client • The Client displays the information in the browser • Web pages may take long to appear because each page element requires a separate request/response Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d 2/3-Tier Client/Server Architecture • The typical Web Client/Server model is two tier because it has one client and one Server • In the three-tier Client/Server model the third tier includes Server applications that supply information to the Web Server • E.g. a catalog style Web site with search, update and display functions: the catalog database and database management software would make up the third tier Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Server Hardware • Web Servers have more memory, faster hard drives and faster processors (or multiple processors) than desktop machines Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Cost • A high-end desktop PC with 512MB RAM, 3GHz processor, a 200GB IDE drive, a good LCD monitor and DVD/CD-RW drive cost between Rs. 50,000 • A low end Web server might cost around Rs. 150,000 • Companies spend between US$ 1,500 and $2,000 for a Web server • Suppliers of these servers include Dell, Gateway and Hewlett Packard,IBM etc. Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Server Architectures • Server farms refer to large (hundreds, or thousands) of Web servers used to handle daily traffic on large Web sites • A Centralised architecture uses a few very large and very fast computers • A Distributed/decentralised architecture uses a larger number of less powerful computers Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Server Architectures • The Centralised architecture requires • Expensive computers • Is more susceptible to technical problems • If one or a few of the servers are available then a large proportion of the site is unavailable • As a result a backup/recovery plan is essential Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Web Server Architectures • The Distributed/decentralised architecture: • Spreads the risk over a large number of servers • The smaller servers are less expense that larger ones (the cost of 100 smaller servers is usually less that the cost of one large one) • Additional hubs and switches are required to link the servers together and to the Internet • These sites might also use load-balancing systems which are an additional cost Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Load Balancing Systems3 • A load-balancing switch: • A piece of network hardware that monitors the workload of servers attached to it • Assigns incoming web traffic to the server with the most available capacity at the given time Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Why Load-balance? • Allows Highly-Trafficked Sites To Maintain Fast Response Times • Server Redundancy - If An Application Server Goes Down, Your Site Stays Up • Better Site Performance = Better User Experience = Better Sales Results • Readies Your Hosting Configuration For Traffic Growth & Intense Traffic Spikes Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Simple Load-Balancing • Traffic enters the site from the Internet through a router (not shown in diagram) • This traffic is then directed to the appropriate Web server by the load-balancing switch www.inetu.com Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Load Balancing Systems Cost • Load-balancing switches and software cost between US$10,000 and US$50,000 www.inetu.com Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d • It should now be clear what hardware and server software is required to construct a Web site • In this next section we will discuss the client-side and server-side software used to construct Web sites Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Client-side Technologies • Client-side Web technologies include: • HTML • XML • JavaScript • VBScript • Java Applets Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Server-side Technologies • Server-side Web technologies include: • Perl/CGI • JSP • PHP • Microsoft ASP/ASP.NET Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d • In addition to the client-side and server-side software that has just been discussed, it is also important to know the e-commerce software that is available to businesses, who either want to host their own Web sites, or want to outsource the hosting function Designing, Building and Evaluating Web Sites
Constructing a Web Site Cont’d Finding and Evaluating Web Hosts • When a company takes on the responsibility of hosting their own Web site this is called self-hosting • Small and mid-size businesses tend to outsource to a third party, i.e. use a Web hosting service provider • These third parties are called Internet Service Providers (ISPs), Commerce Service Providers (CSPs), Managed Service Providers (MSPs) or Application Service Providers (ASPs) Designing, Building and Evaluating Web Sites