Servers for E-Business
MGS 659 Dr Rao Chapter 6
1
Learning Objectives
„ Identify Components of an e-commerce platform
„ Select appropriate platforms for various situations.
„ Distinguish between critical and non-essential
features of an e-commerce architecture.
„ List the components necessary for front-end and
back-end of e-commerce transaction systems
„ Elicit the steps involved in establishing an ecommerce web site.
2
Overview
„ Platform = Hardware + basic software
required to run the computer.
„ Functions of a computer:
1.
„ 2.
„ 3.
„ 4.
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Interface logic,
Business application,
Database and
Display.
3
Computing architecture
Shift from: Centralized mainframe computing
To: Distributed processing of clients and server
Two-tier architecture:
„ Server, at the back end,
„ manages the essential functions like disk drives,
„ printers, network traffic and some applications.
„ Clients’ computers are at the user’s end, mainly personal computers,
which run applications. They display data in text mode or graphical
user interface.
Multi-tier architecture:
„ Additional layers of computer servers have been added between the
client and the server in the
„ Network.
4
Phases of e-commerce architecture
„ First step: Placing the company’s information about
products, prices, promotional schemes etc. on the web
using a web server.
„ Second step: Receiving orders, managing inventory and
collecting invoices.
„ Third step: Redesigning business process and supply
chain in order to take full advantage of the technology.
(Most challenging part as multiple components on
multiple platforms have to be integrated). Achieved
through Enterprise Resource Planning, Supply Chain
Management and Customer Relationship Management.
5
Basic e-commerce architecture
6
Overview of computing Platforms
„ In the 1960s –Mainframe computing,
centralized operations
„ Next, mini computers
„ 1980s – Client/Server architecture
„ Presently – heterogeneous Internet platform.
7
Host-Based Platform
„ Centralized computing (one main server and many
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dummy terminals)
A single powerful computer server performs all the
important functions.
Dummy computer terminals are at the other end, used
for requesting a task or displaying results.
No processing is done at the dummy terminals. Only
display is done here.
A database engine on the server provides shared
data processing functions to all other applications.
Jobs are executed in batches.
Often, Front-end processor (FEP) is inserted between
the two computers for connection and authorization
services.
8
Client/Server Platform
„ Distributed computing (between one server and many
clients).
„ In a traditional C/S system, the server performs only
database function, while the client carries out the
other three.
„ Fat client- display + interface logic, business
application, significant amount of database
processing.
„ Thin client- display + interface logic only
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Host Vs Client server systems.
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Differences between a host-based
system and a C/S system
„ Client in a C/S system is a much powerful
computer, usually a personal computer or
computer workstation.
„ Client performs larger amount of functions.
„ The interface in C/S system through graphical
user interface.
„ Depending on the application, the network
capacity may be high or low.
11
Technologies used on the local
area networks include
„ Communication protocols: Transmission Control
Protocol/ Internet Protocol (TCP/IP), Novell network
protocol (SPX/IPX), Sequenced Package Exchange
(SPX).
„ TCP/IP - a suite of communications protocols used to
connect hosts on the Internet.
„ In-built into UNIX operating systems, SUN Solaris
and Linux.
12
World Wide Web Platform
„ WWW - a subset of wide area network.
„ Private or leased lines for implementing C/S system
in a wide area network.
„ WWW is a vast distributed network of millions of
servers where information is stored and which can be
accessed and retrieved from other computers.
„ Language used for web pages – HTML (Hyper Text
Markup Language)
„ TCP/IP followed for sharing and sending of data from
the web servers to the browsers at the client’s end.
13
WWW as an special case of C/S system
„ a n-tier distributed C/S system.
„ Web servers – dedicated machines acting as
repositories for web pages. Web servers consist
of hardware, O.S., web server software..
„ At the client’s end, the software required to view
the web pages on personal computer is called a
browser.
„ Browsers – Netscape Navigator, Microsoft
Internet Explorer, and Opera Browser, and
mobile micro-browser.
14
Internet mechanism
„ In WWW, any web server on any platform can interact
with any browser running on any client machine
connected through the Internet.
„ Linking the clients and server through dial-up
connection, a privately leased line, digital subscriber
line (DSL) or cable modem.
„ Access to the internet provided by Internet Service
Providers like AOL, CompuServe, Prodigy or
Telephone companies.
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Internet – fig 6-4
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Components of an e-commerce
website
1. Informational website hosted on a web server
on the company’s side
2. Web server on the visitor’s side
3. Access to e-mail for both the business and
the client
4. the core editing/development tools
associated with the platform.
17
Fig 6-5 heterogeneous system.
18
Additional functionalities of the
website
„ Secure transactions using sophisticated
software and hardware.
„ Links to back-end processing.
„ Links to external credit-checking and
payment processing centers.
„ Delivery mechanism linking to the
warehouse and shipping center.
19
Complex e-commerce architecture
20
Enterprise Resource Planning (ERP),
Supply Chain Management (SCM),
Customer Relationship Mgmt (CRM)
provide competitive advantage to a firm
vis a vis its competitors today.
21
Fig 6-7Integrated e-business
22
Components of E-commerce
„ Clients (with access to internet)
„ Internet
„ Routing devices at the boundary of the enterprise.
„ Extra devices to defend the perimeter against potential
hackers.
„ Web server / commerce server
„ Application servers (in advanced systems)
„ Back-end transactional software
(includes TP monitors, database management system and
data warehouse).
23
TP monitor
„ A program that monitors a transaction as it
passes from one stage in a process to
another.
„ It ensures that a transaction is completed
successfully, or roll-back occurs, partial
transactions are prevented.
„ TP is important in three-tier architectures that
employ load balancing.
„ TP coordinates ERP, SCM and CRM.
24
Web Browsers
„ Not all browsers support all web functionalities.
„ Originally Lynx was developed to display limited
text.
„ Later, graphics was added.
„ Later iterations, a range of functionalities added, at
the cost of computing resources and slower
download.
25
Major players in the browser market
„ Microsoft Internet Explorer (I.E.) and Netscape
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Navigator.
I.E. is more integrated with desktop operating system
(mainly Windows), which is also a Microsoft product.
Netscape did not have a new product release between
1998 and 2000 and lost the number one position, which
it held only three years ago to I.E.
I.E now claims more than 3/4th of the market.
Both are freely available for the end user.
26
Microsoft Internet Explorer
„ Browser for display of web pages.
„ NetMeeting for collaboration
„ FrontPage Express for building Web pages.
„ Outlook Express for fully functional e-mail.
„ Supports FTP, Gopher, NNTP, JavaScript,
ActiveX controls etc.
„ Java applets can be executed in version 5.x
„ I.E. 6.0 strongly supports VBScript
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Netscape Communicator
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Netscape Navigator browser
Netscape Messenger (fully configurable e-mail client)
Netscape Composer (HTML editor)
Netscape Conference (for telephony interface)
Collabra discussion (for news groups)
Netcaster (for push technology)
Add-ins compatibility.
Java applets can be executed.
Netscape 6.x based on Mozilla (an open-source code)
supports XML, though less stable.
28
Other Browsers -Opera software
„ Optimizes space and speed.
„ Strict adherence to HTML standards
„ Sophisticated and speedy web-browsing with news and
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e-mail
Secure 128-bit SSL encryption.
Ideal for older machines and mobile computing with less
available memory or disk space.
Soon the BeOS, Linux and Mac versions will also be
available.
Freely available for download (in advertising mode) .
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HotJava
„ Java web browser from SUN
„ has small requirements and is designed to
work on a variety of devices.
„ Not widely used
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Microbrowser
„ Wireless devices are constrained computing device
with limited CPU, memory, battery life, and simple
user interface;
„ wireless networks are restricted with low bandwith,
high latency, and unpredictable availability and
stability.
„ wireless subscribers have different needs and
desires than desktop, or even laptop Internet users
„ WAP (Wireless Application Protocol) specification
was developed to address the technical requirements
and market issues unique to the wireless
environment.
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Microbrowser
„ e.g. OpenTV, 4thpass, Nokia, PIXO…
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Mozilla
„ An open source project from Mozilla.org
„ A modular web browser, designed for
standards compliance, performance and
portability
„ Platform-independent
„ DocZilla- the latest project with enhanced
support for XML and SGML by Finnish
company CiTEC.
33
Web Servers
„ A Web Server is a computer and associated
software that is attached full-time to the internet.
„ The main software component is HTTP
(HyperText Transfer Protocol) server, to process
http requests.
„ Called httpd in UNIX and https in Microsoft
Windows NT/2000.
34
Constraints in selecting a Web
server in an e-commerce project
„ Legacy software
„ Back office
„ Network
„ Administrator preferences
„ Web development skills of the staff
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Selecting a web server
„ Performance – minimum wait time for downloading
„ Development – where initial content can be developed
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and maintenance is not overly difficult.
Security – different levels of access rights to the users.
Multiple types of CPU, hardware and operating system
should be supported.
Multi- platform solution – for longevity of the system
without being tied to one particular CSP.
Clustering capabilities and automatic fail-over.
Stability and reliability.
36
Functionality Checklist
High performance HTTP engine
„ Connections per second or requests per second
„ Bytes per second
„ Round trip or response time
„ Errors
„ Functional compliance with HTTP version 1.1 or later.
„ Scalability of the architecture
„ Integration of clustering for fault-tolerance, load balancing
and reliability
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Functionality Checklist contd..
Interface to the back end applications
„ Common gateway interface (CGI)
„ Cross platform interoperability
„ Java servlets and Java server pages
„ Open database connectivity (ODBC)
„ Remote method invocation (RMI)
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Functionality Checklist contd..
„ Publishing capability
„ Management and administration
„ Availability of server for lengthy operations
without interruptions
„ Ability of the web server to add functionality
and to control the website’s content.
„ Security
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Web server and supported platforms
Apache Web server
Netbsd, unix, aix, os/2, windows nt,
linux, solaris…
Commerce server/400
As/400
Microsoft IIS 5+
Windows 2000+
Lotus Domino Go
Unix, os/2, windows NT, Solaris
iPlanet Enterprise
Unix, AIX, Windows NT…
40
Management issues in selecting a
web server
„ Product feature set, current availability and the likely
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product evolution path.
Security (trade-in with high performance speed)
Built-in database connectivity and the availability of
application development tools.
Manufacturer’s reputation, quality of technical
support, prior experience with a particular
manufacturer.
Purchase price, licensing and maintenance cost.
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Present web server market
„ Apache – 60 % of market share
„ MS Internet Information Server – 19 %
„ Netscape Communications Enterprise server
(now iPlanet Enterprise Server) – 6 %.
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Apache Web Server
From www.apache.org
Available for free
Highly reliable and stable
Available for many platforms, in both binary and source
code format
„ Since, it is open-source, bug-fixes are rapid and timely.
„ Demerits: Production version of server is not very user
friendly, textual user interface.
„ Comanche (Configuration Manager for Apache) is an
effort to have GUI for users, across various platforms.
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Microsoft Internet Information
Server
„ From Microsoft a leading supplier of IT.
„ Distributed as a free component with NT server, tuned
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for performance on the Intel platform.
Personal Web Server (PWS) for small scale personal
use on Windows 95 and 98.
IIS runs on a single platform (Intel processors on
Windows NT OS).
Many add-ins available (database access tools, emails, security etc.)
Serious security questions
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IIS and Management console
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iPlanet Enterprise Server
„ From Netscape Communications (part of AOL now)
„ The Netscape Enterprise administrative console is intuitive
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to use, manage and configure.
Supports a range of platforms including Sun Solaris and
Windows NT.
Highly stable, seldom requires re-booting.
Comparable to the other two dominant servers in the
market.
Configure through Web User Interface (WUI).
WUI can be used to set up the server with I.E. or Netscape
Navigator browser.
Supports Java applets.
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IBM Lotus Domino Server
„ From the stable of IBM.
„ Now being supplanted by IBM HTTP Server
powered by Apache.
„ Offers integrated messaging and web
application software platform for growing
companies seeking improved customer
responsiveness and streamlined business
processes.
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Monitoring Web Server
Performance
„ Overall network traffic
„ Performance of web server software and
platforms.
„ The load generator (clients)
„ Workloads
„ Measurement and metrics
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Performance Planning and
Monitoring Tools
„ Analysis of logs of active servers
„ Instrumentation of network
„ Server operating systems
„ Web software
„ Laboratory testing (benchmark)
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Sample Monitoring Tools
„ Webstone from Mindcraft
„ WebBench 3.0 by Ziff Davis
„ SPECweb96 from Standard Performance
Evaluation Corporation
„ Web Capacity Analysis Tool (WCAT) and
InetLoad from Microsoft
„ WebSizr and WebCorder from Technovations
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Log analysis (for business intelligence)
„ Recording the date and time a visitor visits and
leaves the page
„ Net.Analysis and CartSmarts from Net.Genesis
„ Aria by Andromedia (part of Macromedia)
„ WebTrends
„ With recent failure of dot coms, log analysis has
become even more important. Number of
software vendors providing these solutions is
increasing rapidly.
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Application Servers and Database Servers
„ Advanced e-commerce websites will have
additional layers of servers
Application Servers,
Mail servers,
Certificates server,
Multi-media server,
Database Servers
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Application Server
„ An extension of middleware solution
„ Introduced in order to isolate the business
logic in projects
„ Facilitates multi-tier applications with flexible
connections.
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Checklist for buying Application software
„ What platforms are supported by the software?
„ Manufacturer’s present and future business risk (going
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concern).
What programming language interface does the application
server support?
What portion of existing applications portfolio will have to be
re-written to accommodate the new environment.
What interfaces to the existing database management
system are feasible?
Direct and indirect costs of purchasing the software, future
incremental costs
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Current trends
„ Most vendors now focus on e-commerce
integration and e-business
„ (database
integration with ERP,
Accounting Systems, OLAP, CRM, SCM
etc.)
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Enterprise Resource Planning
(ERP)
„ Was Inward looking now moves to Outward
looking system
„ For full integration of all the activities of a firm and
improve efficiency of workflow.
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Supporting technologies
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HyperText Transfer Protocol (HTTP)
Common Gateway Interface (CGI)
Practical Extraction & Reporting Language (PERL)
Application Service Provider (ASP)
Active Server Page (confusingly, also ASP)
ActiveX
Java applets
Java Servlets
Java Server Pages (JSP)
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Supporting technologies contd..
„ Component Object Model (COM and COM+)
„ Distributed Component Model (DCOM)
„ Common Object Request Broker Architecture
(CORBA)
„ JavaBeans
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HyperText Transfer Protocol (HTTP)
„ Underlying set of rules / protocols used by the
World Wide Web.
„ It determines how messages are formatted
and exchanged
„ How should the web servers and browsers
react to various commands.
„ In its secure mode https with certificates.
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Common Gateway Interface (CGI)
„ A set of standards for transferring data
between a web server and a CGI program
„ A standard way for web servers to interact
dynamically with users.
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Practical Extraction & Reporting
Language (PERL)
„ A programming language for processing text.
„ Still is dominant tool to write CGI scripts on
UNIX platform.
„ Open interpreted language
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Application Service Provider (ASP)
„ An user does not have to purchase the
application but uses the applications at the
service provider’s server remotely.
„ Has serious security implications
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Active Server Page
(yes, also ASP)
„ A specification for viewing dynamically created
web page that utilizes ActiveX scripting.
„ Customized page for an individual viewer.
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ActiveX
„ A set of scripts or programs that run on the user’s
machine rather than on the web server.
„ They are the rules for how applications should
share information dynamically.
„ E.g. Java applets, Java scripts, ActiveX controls.
„ These ActiveX controls can be written in many
languages (C, C++, VB, Delphi & Java).
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Java applets
„ Java applets are programs executed from
within another application, e.g. a web browser
„ Unlike an application, applets cannot be
executed directly from the operating system.
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Java Servlets
„ Similar to applets, but run on servers
„ Similar to CGI programs, but unlike CGI we
do start the program only once in a session
and it lies in memory for next use.
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Java Server Pages (JSP)
„ Similar to Active Server Pages
„ Differs from ASP as the language here is
Java instead of Microsoft Visual Basic.
„ Advantages include portability, modularity,
security and scalability.
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Component Object Model
(COM and COM+)
„ A model for binary code that enables
programmers to develop objects that can be
accessed by any other COM-compliant
application.
„ A framework for developing and supporting
program component objects.
„ Both OLE and ActiveX are based on COM.
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Distributed Component Model
(DCOM)
„ An extension of COM
„ A set of Microsoft program interfaces in which
client program objects can request services
from server program objects on other
computers in a network.
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Common Object Request Broker
Architecture (CORBA)
„ Allows common objects (which are pieces of
programs actually), to communicate with one
another, irrespective of the programming language
they are written in or the operating system they run
on.
„ Developed by an industry consortium called Object
Management Group.
„ Interface through Inter-ORB Protocol (IOP)
„ On the internet, communicate through Internet InterORB Protocol (IIOP)
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JavaBeans
„ Specification developed by Sun Microsystems
on how Java objects should interact.
„ Similar to ActiveX controls of Microsoft.
„ Differs from ActiveX as JavaBeans can be
developed only in Java but can run on any
platform, whereas ActiveX controls can be
developed in any programming language, but
run only on Windows platform.
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Developing an E-Commerce
platform
„ One of most important decisions
„ Build,
„ Buy,
„ Rent
„ e-commerce solutions?
„ Where
to start?
„ Scope of the project?
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Deployment Practices
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Alternative scenarios
„ Informative site (no transaction capability), mainly
static pages.
„ For small businesses - Transaction processing
through a CSP.
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OLM with Miva Order has a web-based order
processing system.
ZShops from Amazon.com
E-BizBuilder
Yahoo!Store from Yahoo! Inc.
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Selecting a Commerce Service
Provider (CSP)
Factors that facilitate the building of the site
2. Factors that enhance the image of the
vendor
3. Factors that facilitate transactions
4. Factors that expedite shipping and
payment.
1.
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Factors facilitating the building
of the site
„ Portability of the site
„ Bandwidth of the host site
„ Maximum number of items in the catalog
„ Types of servers used
„ Support and back up systems offered
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Factors that enhance the image
of the vendor
„ Flexibility of site-building process
„ Look and feel of the site
„ Promotional capabilities (opportunities for
cross-selling, referral, affiliate program etc.)
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Factors that expedite
transactions
„ Order notification
„
(via e-mail, paging, fax, etc.)
„ Administration security
„
(encryption, firewalls)
„ e-Mail capabilities
„
(FAQ, Support, return…)
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Factors that facilitate shipping
and payment
„ Automatic tax calculation
„ Payment options
„
(credit card, cybercash etc.)
„ Calculation of shipping charges
„
(base and weighted)
„ International trade
„
(cross border, in various currencies)
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Pricing structure of a service
depends upon
„ Number of items listed
„ The bandwidth available or used
„ The storage space
„ Number of e-mail accounts provided
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Evaluation criteria for an
enterprise commerce server
„ Functionality (User interface, security, payment services, OLAP
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etc.)
Cost (of acquisition, license fee, application development,
customization, additional hardware and networking devices).
Time to market
Ease of use for developers, content managers and customers
Performance from an internal and customer perspective
Extensibility – the ability to integrate with third-party add-ons.
Flexibility and nimbleness
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Elements of a planning pipeline
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Collection of product information
Merchant information
Shopper information
Order initialization
Order check
Item pricing
Item price adjustment
Order total
Shipping arrangement
Handling arrangement
Taxation
Inventory management
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Elements of purchase pipeline
„ Checking the order
„ Checking the payment
„ Accepting the contract
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E-Commerce Solutions
Company size
customization
hosting
package
Transaction
volume
Nature of site
Small
Low
ISP
Custom
None
Information site
Small
Medium
ISP
Entry
Low
Entry-level
transactions
Small
High
ISP
Entry+
Low
High impact,
low budget
Medium
Low
CSP
Package
Low
Low impact,
supp. Channel
Medium
Medium
Host
Package+
Medium
Important
medium budget
Medium
High
Host/CSP
Custom
High
High impact
high budget
Large
Low
CSP
Integrated
Package
Medium
Low impact
supp. Channel
Large
Medium
Host
Integrated
Package+
High
Strategic
integration
large
high
Host/CSP
Components
Custom
High
Strategic
competitive
84