ACS 3907 E-Commerce. Instructor: Kerry Augustine February 6 th 2018

Transcription

1 ACS 3907 E-Commerce Instructor: Kerry Augustine February 6 th Pearson Education, Inc. Publishing as Prentice Hall 1

2 E-Commerce Design Architecture Part 1 Client/server architecture Two-tier vs. three-tier architecture Four-tier architecture Web server software/ Site management tools E-Commerce merchant server platform Hardware platform E-Commerce site tools/ Personalization tools Mobile Commerce (M-Commerce) architecture Cloud Computing 2014 Pearson Education, Inc. Publishing as Prentice Hall 2

3 Client/Server Architecture Model of computing where roles and responsibilities are distributed between servers and clients Two-Tier Architecture (1) Client (2) Server + Database (1) Client (2) Server (3) Database Three-Tier Architecture 2014 Pearson Education, Inc. Publishing as Prentice Hall 3

4 Client/ Server Architecture Front-end (client) systems are those processes with which a user interfaces, and over which a customer can exert some control. For an ebusiness, front-end systems are the Web site processes that customers use to view information and purchase products and services Pearson Education, Inc. Publishing as Prentice Hall 4

5 Client/ Server Architecture Back-end (server) systems are those processes that are not directly accessed by customers. Back-end systems include the business s TPS and MIS systems that handle the accounting and budgeting, manufacturing, marketing, inventory management, distribution, order-tracking, and customer support processes Pearson Education, Inc. Publishing as Prentice Hall 5

6 Client/Server Architecture (cont.) Strictly speaking, clients and servers refer to software Client s tasks: Sends requests to servers Display results from server to user Server s responsibilities: Satisfies requests May consult other sources May fail to satisfy requests Servers cannot initiate dialog with clients May exist on same physical machine or separate machines 2014 Pearson Education, Inc. Publishing as Prentice Hall 6

7 Client/Server Architecture (cont.) Servers may respond to multiple clients Clients may send requests to multiple servers Examples of servers: Mail server manages Database server stores info on customers, products, prices Web server delivers HTML content to clients Ad server maintains web-enabled DB of ad banners, allowing customized/personalized display of ads based on customer behaviour and characteristics User application components: presentation, processing, data How to divide up components in architecture? 2014 Pearson Education, Inc. Publishing as Prentice Hall 7

8 Advantages of Client/Server Architecture Scalability Increase/decrease computing capacity easily by adding more clients or servers Interoperability Clients, servers, database can be run on different operating systems Reliability Failure of one component in network most likely does not shut down whole system More elaborate GUIs Can dedicate clients computing resources solely for GUI management 2014 Pearson Education, Inc. Publishing as Prentice Hall 8

9 Disadvantages of Client/Server Architecture Complexity Many machines must work together to communicate and coordinate; Systems must be designed carefully Need for specialized training Development and support staff require specialized knowledge and experience Network management tools less robust These tools are still new relative to other technologies 2014 Pearson Education, Inc. Publishing as Prentice Hall 9

10 Considerations for Choosing Architecture Design System-related: Complexity of the application Level of integration required Process-related: Development time required Flexibility and maintenance of system Client/Users-related: Number of users User s geographical dispersion Nature of networks and transaction needs of the application Response times 2014 Pearson Education, Inc. Publishing as Prentice Hall 10

11 Two-Tier Architecture Most common implementation: Client: presentation, processing Server: processing, data Client responsible for functionality and business logic Server handles data-intensive tasks via database engine (integrity checks, querying) Most common language of communication: SQL Requires tight linkage between server and client 2014 Pearson Education, Inc. Publishing as Prentice Hall 11

12 Three-Tier Architecture Clients are responsible for presentation only Middle-tier servers: Handle data processing Act as clients and send requests to other servers Back-end server dedicated to data Communication via remote procedure calls (RPC) Can be accomplished in Java, C, etc. Client requests specify parameters and return data structures, and do not need to speak the server s language 2014 Pearson Education, Inc. Publishing as Prentice Hall 12

13 Three-Tier Architecture RPC RPC 2014 Pearson Education, Inc. Publishing as Prentice Hall 13

14 Advantages 2-Tier Fast application development; low initial development efforts required 2-tier tools are extremely robust Good for iterative prototyping and rapid application development techniques 3-Tier Development expertise can be more focused to specific tiers Separation allow parallel development Data and process changes do not affect clients Middle-tier servers help decrease and localize network traffic Reduce data needs (memory, processing, disk storage) for clients Modularity, leading to higher code reuse, lower maintenance and migration costs when switching client applications Lower subsequent development efforts 2014 Pearson Education, Inc. Publishing as Prentice Hall 14

15 Disadvantages 2-Tier Not suited for dispersed, heterogeneous environments (e.g. cross-departments, cross-platforms) Not suited for environments with rapidly changing business rules Difficulties with version control and redistribution of client application Proliferation of end-user query tools can compromise database server security (could amend via middleware) Client tools and SQL middleware are proprietary Higher subsequent development efforts High migration costs for client tools 3-Tier 3-tier tools/platforms are more complex; require more planning More complicated code, thus, increases chance of system failure Requires network traffic management, server load balancing, fault tolerance High initial development effort needed 2014 Pearson Education, Inc. Publishing as Prentice Hall 15

16 Four-Tier Architecture The Web server is physically separated from the application server. This is often done for security reasons, where the Web server is deployed into a perimeter network and accesses the application server located on a different subnet. In this scenario, you might implement a firewall between the client and the Web tier, and another firewall between the Web tier and the application or business logic tier. Consider the 4-tier pattern if security requirements dictate that business logic cannot be deployed to the perimeter network, or you have application code that makes heavy use of resources on the server and you want to offload that functionality to another server Pearson Education, Inc. Publishing as Prentice Hall 16

17 Example - Four-Tier Architecture Client Tier Web Tier Application Tier Database Tier Internet Website: This application is used with popular and recent browsers on desktop and mobile devices and is structured in 4 layers: client (browser), UI (Web), Application logic (Services) and Database. Intranet Application: this application is used on the current corporate browser (Internet Explorer 8) and is also structured in 4 layers. Desktop Application: this application is deployed directly to the desktop using Click Once and connects to a service layer for application logic and then a database layer. These will be internal applications only Pearson Education, Inc. Publishing as Prentice Hall 17

18 Web Server Software Apache Leading Web server software (60% of market) Works with UNIX, Linux operating systems Microsoft s Internet Information Server (IIS) Second major Web server software (20% of market) Windows-based 2014 Pearson Education, Inc. Publishing as Prentice Hall 18

19 Table 4.4, Page Pearson Education, Inc. Publishing as Prentice Hall 19

20 Basic tools Site Management Tools Included in all Web servers Verify that links on pages are still valid Identify orphan files Third-party software for advanced management Monitor customer purchases, marketing campaign effectiveness, and so on WebTrends Analytics 10, Google Analytics 2014 Pearson Education, Inc. Publishing as Prentice Hall 20

21 WebTrends Analytics 2014 Pearson Education, Inc. Publishing as Prentice Hall 21

22 Dynamic Page Generation Tools Dynamic page generation: Contents stored in database and fetched when needed Common tools: CGI, ASP, JSP, ODBC (Open Database Connectivity) Advantages Lowers menu costs Permits easy online market segmentation Enables cost-free price discrimination Enables content management system (CMS) 2014 Pearson Education, Inc. Publishing as Prentice Hall 22

23 Application Servers Web application servers: Provide specific business functionality required for a Web site Type of middleware Isolate business applications from Web servers and databases Single-function applications being replaced by integrated software tools that combine all functionality needed for e- commerce site 2014 Pearson Education, Inc. Publishing as Prentice Hall 23

24 E-commerce Merchant Server Software Provides basic functionality for sales Online catalog List of products available on Web site Shopping cart Allows shoppers to set aside, review, edit selections, and then make purchase Credit card processing Typically works in conjunction with shopping cart Verifies card and puts through credit to company s account at checkout 2014 Pearson Education, Inc. Publishing as Prentice Hall 24

25 Merchant Server Software Packages Integrated environment that includes most of functionality needed Key factors in selecting a package Functionality Support for different business models Business process modeling tools Visual site management and reporting Performance and scalability Connectivity to existing business systems Compliance with standards Global and multicultural capability Local sales tax and shipping rules 2014 Pearson Education, Inc. Publishing as Prentice Hall 25

26 Web Services and Open-Source Options Options for small firms Hosted e-commerce sites Offer site building tools and templates Example: Yahoo s Merchant Solutions Open-source merchant server software Enables you to build truly custom sites Requires programmer with expertise, time 2014 Pearson Education, Inc. Publishing as Prentice Hall 26

27 EC Suites: SiteCore 11 (Formally MS Commerce Server 2009 Acquired Nov-2013) Developer edition: ~$7K Enterprise edition: ~$120K Both templates contain a contemporary presentation skin for the out-of-the-box default Web site and mobile site integrated into MS SharePoint, with optional sample data. Allows for different marketing campaigns for different brands or different customer segments or both. Comes with built-in discounts, advertisement management, and a direct mailer, with expression-based lists; all with multi-lingual support. Offers an integrated data warehouse across customer profile, catalog, order, marketing, and Web log data Pearson Education, Inc. Publishing as Prentice Hall 27

28 EC Suites: IBM WebSphere Commerce Express: ~$7000 Professional: ~$100K Enterprise: ~$200K 2014 Pearson Education, Inc. Publishing as Prentice Hall 28

29 The Hardware Platform Hardware platform: Underlying computing equipment needed for e-commerce functionality Objective: Enough platform capacity to meet peak demand without wasting money Important to understand the factors that affect speed, capacity, and scalability of a site 2014 Pearson Education, Inc. Publishing as Prentice Hall 29

30 Right-Sizing Your Hardware Platform: The Demand Side Customer demand: Most important factor affecting speed of site Factors in overall demand: Number of simultaneous users in peak periods Nature of customer requests (user profile) Type of content (dynamic vs. static Web pages) Required security Number of items in inventory Number of page requests Speed of legacy applications 2014 Pearson Education, Inc. Publishing as Prentice Hall 30

31 Scalability: Right-Sizing Your Hardware Platform: The Supply Side Ability of site to increase in size as demand warrants Ways to scale hardware: Vertically Increase processing power of individual components Horizontally Employ multiple computers to share workload Improve processing architecture 2014 Pearson Education, Inc. Publishing as Prentice Hall 31

32 Factors in Web Site Optimization Figure 4.10, Page Pearson Education, Inc. Publishing as Prentice Hall 32

33 Table 4.8, Page Pearson Education, Inc. Publishing as Prentice Hall 33

34 Table 4.9, Page Pearson Education, Inc. Publishing as Prentice Hall 34

35 Mobile Commerce (M-Commerce) Takes traditional EC models onto wireless platform Already popular in Asia and Europe Wireless technologies: 4G = fourth-generation wireless wifi = wireless local area networks Bluetooth = short range radio frequency web devices Ultrawide band = wireless USB technology Allows large file transfers over short distances Zigbee = connect devices to each other but at longer range and with lower power requirement than Bluetooth 2014 Pearson Education, Inc. Publishing as Prentice Hall 35

36 GSM Cellular system: GSM vs CDMA formerly: Groupe Spéciale Mobile (founded 1982) developed by the European Telecommunications Standards Institute (ETSI) now: Global System for Mobile Communication As of 2014 it has become the default global standard for mobile communications - with over 90% market share, operating in over 219 countries and territories AT&T and T-Mobile GSM carriers put customer information on a removable SIM card CDMA Code Division Multiple Access U.S., Sprint, Verizon and U.S. Cellular owned by chipmaker Qualcomm CDMA carriers use network-based white lists to verify their subscribers 2014 Pearson Education, Inc. Publishing as Prentice Hall 36

37 3GPP Cellular system: 3GPP 3rd Generation Partnership Project (3GPP) seven 3GPP Organizational Partners are from Asia, Europe and North America. Their aim is to determine the general policy and strategy of 3GPP 2014 Pearson Education, Inc. Publishing as Prentice Hall 37

38 Cellular system: LTE LTE 3rd Long-Term Evolution, commonly marketed as 4G LTE, is a standard for wireless communication of highspeed data for mobile phones and data terminals. based on the GSM/EDGE (Enhanced Data rates for GSM Evolution) and UMTS (Universal Mobile Telecommunications System) /HSPA (High Speed Packet Access) network technologies, increasing the capacity and speed using a different radio interface together with core network improvements. standard is developed by the 3GPP (3rd Generation Partnership Project) 2014 Pearson Education, Inc. Publishing as Prentice Hall 38

39 Architecture of the GSM system GSM is a PLMN (Public Land Mobile Network) Components MS (mobile station/ mobile equipment) Subscriber Identity Module (SIM) BTS (base transceiver station) MSC (mobile switching center) HLR (home location register) VLR (visited location register) EIR (equipment identify register) AUC (authentication centre) Subsystems BSS (base station subsystem) GSM Inter-Working Unit (GIWU): enables users to alternate between speech and data during the same call RSS (radio subsystem): covers all radio aspects NSS (network and switching subsystem): call forwarding, handover, switching OSS (operation subsystem): n/w management 2014 Pearson Education, Inc. Publishing as Prentice Hall 39

40 Architecture of the GSM system "Gsm structures" by Tsaitgaist 2014 Pearson Education, Inc. Publishing as Prentice Hall 40

41 Cloud Computing Software and storage provided as an internet service and accessed within a web browser Example: , Data storage, skydrive, tax software, flicker, facebook. Radically reduces costs of: Building and operating Web sites Infrastructure, IT support Hardware, software 2014 Pearson Education, Inc. Publishing as Prentice Hall 41

42 Cloud Computing Advantages to Businesses Outsourcing Resources Saves on system design, installation, and maintenance Provides an ability to access corporate systems from any Internet-connected device Increases the data storage capabilities of the firm Data safeguarding responsibility of service provider 2014 Pearson Education, Inc. Publishing as Prentice Hall 42

43 Google Cloud Centre 2014 Pearson Education, Inc. Publishing as Prentice Hall 43