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Transcript
Electronic Commerce
COMP3210
Session 2: Internetworking and the World Wide Web
Dr. Paul Walcott
Department of Computer Science, Mathematics and Physics
University of the West Indies, Cave Hill Campus
Barbados
© 2007 Dr. Paul Walcott
The Department of Computer Science Mathematics and Physics, University of the West Indies, Cave Hill Campus, Barbados
Session Objectives

After completing this session you will be
able to:




Describe the Internet and its history
Describe the World Wide Web (WWW)
Describe some of the software required to
build an e-commerce Web site
Describe the Open System Interconnection
(OSI) model
Session Objectives Cont’d





Describe the use of tools in the construction
of Web sites
Compare and contrast different types of
computer networks
Compare and contrast different methods of
connecting to the Internet
Create a simple Web Page
Create a simple XML document
The Internet



What is the Internet?
The history of the
Internet
The growth of the
Internet
What is the Internet1


The Internet is a large system of interconnected networks that span the globe
Internet-ready computers and personal
digital assistants (palm and pocket PCs)
can access this network2
What is the Internet Cont’d

The Federal Networking Council (FNC)
defines the Internet more formally as the
global information system that3:

is logically linked together by a globally
unique address space based on the Internet
Protocol (IP) or its subsequent
extensions/follow-ons
What is the Internet Cont’d


is able to support communications using the
Transmission Control Protocol/Internet
Protocol (TCP/IP) suite or its subsequent
extensions/follow-ons, and/or other IPcompatible protocols; and
provides, uses or makes accessible, either
publicly or privately, high level services
layered on the communications and related
infrastructure described herein
What is the Internet Cont’d

The Internet allows:







communication by e-mail
the reading of on-line newspapers, academic journals
and books
the joining of discussion groups,
participation in simulations and games
downloading of software, electronic books, movies
and music
businesses to market and sell products and services
and exchange information (e-commerce)
And much more …
The History of the Internet1


In the early 1960s the US department of defense
began investigating ways of creating networks of
computers that coordinate and control nuclear
weapons
This network was to withstand attack, so that
even if part of it was down it will continue to
function


This network was to have no central control
These new networks required multiple channels
to send information (leased lines inadequate)
The History of the Internet Cont’d




In 1969 the advanced research agency
(ARPA) used this network model to
connect four computers
This network was called the ARPANET
During the 1970s and 1980s the academic
community contributed to this network
In the late 1980s this network became the
Internet
The History of the Internet Cont’d
www.let.leidenuniv.nl/history/ivh/chap2.htm
Internet Growth1



In 1969 ARPANET (the Internet)
connected 4 computers
In 1990 the Internet connected 300,000
In 1995 the intranet was privatised


The structure was based on four network
access points (NAPs) operated by different
telecom companies in the US
As the Intranet grew, more NAPs were added
Internet Growth Cont’d

The NAPs began selling Internet access rights to
large customers





Internet service providers (ISPs) sold on the service
to small businesses and individuals
Growth in Internet hosts rose from under 10
million in 1995 to over 180 million in 2004
Millions of people now use the Internet
Billions of dollars are exchanged from the sales
of products and services
Estimated number of Web sites is 40 million and
billions of web pages
The World Wide Web



www.ransen.com/Repligator/Spider.htm

What is the World
Wide Web?
What is hypertext?
Hypertext markup
language (HTML)
example
What types of Web
sites exist?
What is the World Wide Web

The World Wide Web (WWW) was an
Internet-based hypertext project that
allowed global information sharing2


It is software that runs on machines
connected to the WWW
The WWW is based on two concepts1:


Hypertext and
a graphical user interface (a Web browser)
What is Hypertext1

In 1945, Vannevar Bush wrote an article in
the Atlantic Monthly describing a system,
called Memex, that would store all a
person’s books, records, letters and
research results on microfilm
(http://www.theatlantic.com/doc/194507/bush/1)

Microfilm and indexes would then be used
to quickly access this information
What is Hypertext Cont’d

In the 1960s, Ted Nelson described a similar
system (http://www.livinginternet.com/w/wi_nelson.htm):


He incorporated a page linking system called
hypertext
Tim Berners-Lee wrote a hypertext server in 1989
which


stored files written in hypertext markup language (HTML)
allowed other computers to read these files
What is Hypertext Cont’d

Tim Berners-Lee
hypertext server was
called httpd and his
client browser
“WorldWideWeb”
which is illustrated in
the picture
HyperText Markup Language




HTML is a markup language that includes a set of
tags attached to text
These tags describe the relationship between text
elements
A hypertext link (or hyperlink) points to another
location in the same or another HTML document
(that might be stored on the same or another
computer)
Given below is an example of a simple HTML
document.
HTML Example
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/2002/REC-xhtml1-20020801/DTD/xhtml1strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<!-- This is a simple XHTML 1.0 document -->
<head>
<title>Hypertext Markup Language (HTML) Example</title>
</head>
<!-- This is the body part of the document -->
<body>
<p>An XHTML 1.0 document must include:</p>
<ol>
<li>A HEAD element</li>
<li>A BODY element</li>
Creates a numbered list
</ol>
</body>
</html>
of items
HTML Example Cont’d



This page includes
the paragraph, <p>
tag, and the ordered
list, <ol> tag
The rendered web
page is illustrated on
the right
You will learn more
about XHTML in the
next session
XML Markup Language


XML or Extensible Markup Language is a
markup language that is similar to XHTML
XHTML and XML, however have different
purposes:



XHTML is primarily used to present (display) data,
while
XML is used to describe data
An example of a simple XML document which
stores course information is illustrated below:
XML Example
<?xml version="1.0"?>
<!-- The syntax for comments is the same as in XHTML -->
<courses>
<course id="1">
<code>COMP3210</code>
<name>Electronic Commerce</name>
<credits>4</credits>
</course>
</courses>
Graphical Interface for Hypertext


A Web browser is a graphical user interface used to read
and navigate through files written in HTML
In 1993 the first graphical web browser was developed;
called Mosiac
(http://archive.ncsa.uiuc.edu/SDG/Software/Mosaic/NCSAMosaicHome.html)

Popular web browsers include:
 Microsoft Internet Explorer
(http://www.microsoft.com/windows/ie/default.mspx)
 Netscape (http://browser.netscape.com)
 Mozilla Firefox (http://www.mozilla.com/firefox/)
Mosiac Web Browser
Internet Explorer Web Browser
Netscape Web Browser
Mozilla Firefox Web Browser
Hypertext Servers (Web Servers)1

There are several Web servers available today,
however the most popular are (April 2006
survey)4,8:



Apache HTTP Server 67.11% (down from 69.01% in
2004)
Microsoft Internet Information Server (IIS) 20.61%
(down from 23.26% in 2004)
Sun Java System Web Server (JSWS) (former names
are Sun One, iPlanet Enterprise Server and Netscape
Enterprise Server) 2.50% (up from 0.86% in 2004)
Apache (“A Patchy” Server)





Developed in 1994 by Rob McCool
The original core system has many patches
applied to it, and thus its name
Apache has dominated the Web since 1996
Freely available
Runs on many operating systems including
FreeBSD-UNIX, HP-UX, Linux, Microsoft
Windows, SCO-UNIX and Solaris
Microsoft Internet Information
Server (IIS)




Comes bundled with Microsoft Windows Server
operating system
IIS used on many corporate intranets (Microsoft
standard product)
Originally written to run on Windows NT and
Windows 2000; runs on Windows 2003 Server
and Windows XP
Supports ASP, ActiveX Data objects and SQL
queries
Sun Java System Web Server




This is a descendant of the original NCSA server
Cost US$1500-per-CPU licensing fee
Runs on HP-UX, Solaris and Windows
Is ODBC compatible (i.e. full access to ODBC
compliant databases)

ODBC is short for Open DataBase Connectivity, a
standard database access method which allows access
to data from any application
(http://www.webopedia.com/TERM/O/ODBC.html)
Web Site Types

There are numerous different types of Web sites
including:


Development sites: are used by companies to
evaluate web site designs. The initial investment in
these sites are small since they use existing hardware
(i.e. no special hardware is purchased)
Intranets: these are corporate networks that hold
documents such as internal memos, corporate
handbooks, expense account worksheets, budgets and
newsletters
Web Site Types Cont’d


Extranets: which allow external entities, e.g.
suppliers and strategic partners to access a subset of
the information on the Intranet
Transaction-processing: These sites operate 24 hours
a day, seven days a week and require fast, reliable
hardware and e-commerce software

Web sites hosting B2B and B2C activities must have spare
capacity to support an increase in customer volume.
Web Site Types Cont’d

Content-delivery: sites must be available
seven days a week, 24 hours a day and
require fast and precise search engines to help
visitors locate information quickly

These sites deliver content such as news, histories
and other digital information.
Networking



What is a computer
network?
What are some of the
types of networks?
Characteristics of
networks


http://www-structure.llnl.gov/Xray/comp/network.gif

Network topology
Network protocols
Network architectures
What is a Network5

A network is a group of two or more
computer systems linked together
Types of Networks6

There are several types of computer
networks including:

Local-area networks (LANs)


Computers that are geographically close to each
other (in the same building)
Wide-area networks (WANs)

Computers are farther apart than LANs; typically
connected by telephone lines or radio waves
Types of Networks Cont’d

Campus-area networks (CANs)


Metropolitan-area networks (MANs)


These computers are within a limited geographic
area, e.g. a campus
These networks are designed for towns and cities
Home-area networks (HANs)

A network created in a person’s home
Characteristics of Networks5,6

A network is characterised by its:

Topology


Architecture


The geometric arrangement of the computer system
This refers to the two major type of networks, peer-to-peer
or client/server
Protocol

The set of rules and signals used to communicate (e.g.
Ethernet or IBM’s Token Ring)
Network Topologies6

Common network
topologies include:




Star topology
Ring topology
Bus topology
Other topologies
include the:


Mesh topology
Tree topology
http://www.webopedia.com/TERM/s/star_network.html
Network Topologies Cont’d

Network topologies are considered either
logical or physical



The physical layout of a network is its
physical topology
The way signals are routed through a network
is the logical topology
Just because a network has a particular
physical topology does not mean that its
logical topology must be the same
Network Topologies Cont’d

For example:


Twisted-pair Ethernet has a logical bus
topology on a physical star topology layout
IBM’s token ring has a logical ring topology
on a physical star topology layout
Star Topology

In a Star network all nodes are connected
through a central hub


A node is a computer or device, e.g. a printer;
each node has a unique address called the
Data Link Control (DLC) address or the
Media Access Control (MAC) address
The main advantage of the star network is
that a malfunctioning node does not affect
the rest of the network
Star Topology Cont’d

The main disadvantage of the star network
is that:



It requires more cabling than other topologies
(e.g. the ring network), and
If the hub goes down, the network no longer
functions
Standard twisted-pair Ethernet uses a
physical star topology
Ring Topology





Each node in a ring network is connected to two
other nodes to form a closed loop
Messages pass around the ring and each node
reads the message addressed to it
One advantage of a ring network is that it can
span larger distances than other networks (e.g.
bus) because each node regenerates the signal
One disadvantage is that malfunctioning nodes
can make other nodes inaccessible
IBM’s token ring uses a logical ring topology
Bus Topology





The nodes in a bus topology are connected to a
central cable called a bus or backbone
The bus has two end points
One advantage of the bus network is that if one
node goes down the network still functions
One disadvantage of the bus network is it can not
travel as long a distance as say a ring network due
to the diminishing signal strength
Ethernet 10Base-2 and 10Base-5 use the bus
topology
Mesh Topology

In the mesh topology
many redundant
connections exist
between nodes; in a
true mesh, each node
is connected to every
other node
http://www.webopedia.com/quick_ref/topologies.asp
Tree Topology

The tree topology is a
hybrid where groups
of star-configured
networks are
connected to a linear
bus backbone
http://www.webopedia.com/quick_ref/topologies.asp
Architecture6

The two main types
of architecture are


Peer-to-Peer (P2P)
Client/Server
http://www.rebri.org.nz/images/builder-big.jpg
Peer-To-Peer (P2P) Networks


In a P2P network each node has equivalent
capabilities and responsibilities
These networks are simpler than
Client/Server but do not offer the same
performance under heavy loads
Client/Server Networks




In a Client/Sever network each node is either a
client or server
Client computers run applications, but rely on
servers for resources such as files and printing
capabilities
Servers are powerful computers that manage
files, printers or network traffic
This architecture is sometimes called the two-tier
architecture
Network Devices

Several devices are used in networks
including:




Hubs
Switches
Bridges
Routers
Network Devices (Cont’d)
Hub
 A hub is a central connection point for
several network devices
 There are two types of hubs:

An active hub is usually powered


Amplifies and cleans up the signal it receives
A passive hub is not powered

Uses some of the signal strength in order to
operate -- operates over shorter distances
Network Devices (Cont’d)
Switch (or Switching Hub)
 A switch builds a table of the MAC addresses of
the devices connected to it
 When the switch receives the data, the actual
node that the data needs to be sent to is
determined and the data sent to that node

This is the difference between a switch and a hub,
since the hub sends all the messages to all connected
nodes
Network Devices (Cont’d)
Bridge
 A bridge logically separates a single network into
two segments
 This is useful when you have one or more servers
(for example) on the network that are heavily
used and others that are not

By separating the network with a bridge, the
performance of the part of the network that is less
active is not compromised
Network Devices (Cont’d)
Router
 Routing is the process of moving data
through a network using routers
 Routers store information about which
routes packets can take to get to their
destinations on files called routing tables

Only packets with specified destinations will
be routed
The OSI Model9

The Open Systems Interconnect Model (OSI):




provides a fundamental understanding of network
data transmission through a set of guidelines
Promotes interoperability
Describes the tasks a protocol suite (the set of rules
used which allow computers to communicate)
perform
Developed in 1977 by the International Organization
for Standardization (ISO)
The OSI Model (Cont’d)

The OSI model
consists of seven
layers

Each layer performs
a particular function
and passes the result
to the next layer
http://static.howstuffworks.com/gif/osi-model.jpg
The OSI Model (Cont’d)

The Application layer:


Refers to tools that an application can use to
complete a task, e.g. spreadsheet software
requesting a file transfer
Defines how network services interact with
the network

These services include file, print and messaging
services
The OSI Model (Cont’d)

The Presentation Layer:

Responsible for formatting data that will be
exchanged
Data encryption
 Converting character sets
 Data Compression

The OSI Model (Cont’d)

The Session Layer:

Specifies how two computers establish,
synchronise, maintain and end a session
Security authentication
 Data transfer
 Acknowledgements
 Connection release

The OSI Model (Cont’d)

The Transport Layer:





Ensures that data is transmitted error free
Breaks long messages into smaller chunks
and recompiles them
Combines short messages into longer chunks
Logical name resolution
Acknowledges packet receipt
The OSI Model (Cont’d)

The Network Layer:

Defines protocols to ensure that data arrives
at the correct destination

Relies on logical network addresses (e.g. IP
addresses)
The OSI Model (Cont’d)

The Data Link Layer:


Creates, transmits and receives packets
Is responsible for:
the physical address (MAC)
 Creating logical topologies

The OSI Model (Cont’d)

The Physical Layer:

Converts data into electrical signals



i.e. converts 1 and 0 bits to voltages to pass allow
the medium (e.g. a cable)
Determines the amount of media that will be
used
Is responsible for the physical topology
Protocols


Protocols are agreed
formats for transmitting
data between devices6
The protocol determines:




The error checking
required
Data compression
method used
The way the end of a
message is signaled T
The way the device
indicates that it has
received the message
Internet Protocols

There are many protocols used by the
Internet and the WWW, including




TCP/IP
HTTP
FTP
Electronic mail protocols
IMAP
 POP

TCP/IP

The Internet uses two main protocols (developed
by Vicent Cerf and Robert Kahn)

Transmission control protocol (TCP)



Controls disassembly of message into packets at the origin
Reassembles at the destination
Internet protocol (IP)

Specifies the addressing details for each packet

Each packet is labeled with its origin and destination
Internet Protocol version 4 (IPv4)

Uses a 32 bit number to identify each
computer


Called the IP address (4 billion addresses)
IP addresses use the dotted decimal notation,
e.g. 0.0.0.0 or 255.255.255.255
Internet Protocol version 6 (IPv6)


Set to replace version 4
Changes the format of the packets


Removes unused fields
Uses 128 bit number (2128 addresses)

Eight groups of 16 bits
e.g.
CD18:0000:0000:AF23:0000:FF9E:61B2:884D
 To simplify zeroes may be removed


CD18:::AF23::FF9E:61B2:884D
Hypertext Transfer Protocol (HTTP)7



The hypertext transfer protocol (HTTP) was
developed by Tim Berners-Lee in 1991
HTTP was designed to transfer pages between
machines
The client (or Web browser) makes a request for a
given page and the Server is responsible for
finding it and returning it to the client
Hypertext Transfer Protocol (HTTP)


The browser connects and requests a page from the server
The server reads the page from the file system, sends it to
the client and terminates the connection
Request sent to Web server
Web Server
Client
Response sent with files (one for each
Web page, image, sound clip etc.)
File Transfer Protocol (FTP)2

FTP is a protocol that allows a user to:





list files at a remote site
Transfer files between local and remote computers
Using FTP you can not run applications on a
remote site
Also you can only look at the names of the files
on the remote computer; rather than being able to
read them
FTP is still used today; e.g. to transfer large files
between computers, or to upload Web sites
Electronic Mail Protocols


Electronic mail uses the client/server model
The organisation has an email server
devoted to handling email


Stores and forwards email messages
Individuals use email client software to
read and send email (e.g. Microsoft
Outlook, or Netscape Messenger)
Electronic Mail Protocols Cont’d

Simple Mail Transfer Protocol (SMTP)


Specifies format of mail messages
Post Office Protocol (POP)

tells the email server to:
Send mail to the user’s computer and delete it
from the server
 Send mail to the user’s computer and do not delete
it from the server
 Ask whether new mail has arrived

Electronic Mail Protocols Cont’d

Interactive Mail Access Protocol (IMAP)

Newer than POP, provides similar functions
with additional features
e.g. can send specific messages to the client rather
than all the messages
 A user can view email message headers and the
sender’s name before downloading the entire
message


Allows users to delete and search mailboxes
held on the email server
Electronic Mail Protocols Cont’d

The disadvantage of POP


You can only access messages from one PC
The disadvantage of IMAP

Since email is stored on the email server,
there is a need for more and more expensive
(high speed) storage space
Terminal Emulation - Telnet




Telnet is a terminal emulation program for
TCP/IP networks
The telnet program runs on a local machine and
allows connection to a remote machine
Commands entered through the telnet program
will be executed on the Server; this gives the user
the ability to control the Server
To log into the Server a valid username and
password is required
Ping

Ping is a utility for system administrators/
webmasters to allow them to check
network connections
Connecting to the Internet1

http://www.co.delaware.ny.us/links.htm
What are some of the
ways of connecting to
the Internet?
Internet Connection Options

Internet service providers (ISPs) provide several
ways to connect to the Internet, including:





Voice grade telephone lines
Broadband connections
Leased lines
Wireless
The major distinguishing factor is bandwidth (the
amount of data that can be transferred per unit of
time)
Bandwidth and Connections


Symmetric connection: provides the same
bandwidth in both directions
Asymmetric connections: provide different
bandwidths for either direction


Upstream bandwidth (upload bandwidth): the amount
of information that can travel from the user to the
Internet in a given amount of time
Downstream bandwidth (download or downlink
bandwidth): the amount of information that can be
transferred from the Internet to the user in an amount
of time
Voice-grade Telephone Connections



The most common way
to connect to an ISP is
through a modem
(analog) connected to
POTS (plain old
telephone service) lines
The speed of this
connection is 28 to
56Kbps
It was typical for
computers to be shipped
with built-in modems
Broadband Connections


Connections that operate at speeds higher
than 200Kbps are considered broadband
Two of the major broadband connections
for home users and small businesses are:


Digital Subscriber Line (DSL) and
Cable modems
Broadband Connections Cont’d
Digital subscriber line (DSL)
 Uses telephone lines and a
piece of equipment similar
to a network switch
 Both voice calls and an
Internet connection are
provided simultaneously
 The closer you are to the
provider’s central office, the
better the service
 This service is not available
everywhere
http://computer.howstuffworks.com/dsl.htm
Broadband Connections Cont’d

One of the latest broadband technologies is
asymmetric digital subscriber line (ADSL)


Bandwidths from 100-640Kbps upstream and
from 1.5 to 9 Mbps downstream
For businesses a high-speed DSL (HDSL)
is available

768Kbps of symmetric bandwidth
Broadband Connections Cont’d
Cable Modems
 Cable modems connect to the same broadband
coaxial cable that serves cable television
 Upstream bandwidth of 300Kbps to 1 Mbps is
provided and downstream bandwidth of 10Mbps
 Please note that upstream and downstream
bandwidths vary from provider to provider
Broadband Connections Cont’d
DSL v Cable
 DSL is a private line with no competing traffic
 Cable connections bandwidth vary with the user
load (number of subscribers using the service)
 Problems

Web users in rural areas often do not have cable
access and have limited telephone access (low cost
voice-grade lines, rather than data-grade lines) thus
bandwidth is limited (<14Kbps)
Leased-Line Connections


Large firms with large amounts of Internet traffic
can lease lines from telecommunication carriers
Various technologies are used; classified by the
amount of telephone lines they include:




DS0 (digital signal zero) carries one digital signal
(64Kbps)
T1 (or DS1) carries 24 DS0 lines (1.544Mbps)
Fractional T1 (128Kbps and upwards)
T3 (or DS3) carries 30 T1 lines (44.736Mbps)

These connections more expensive than POTS and DSL
Wireless Connections





Satellite
Bluetooth
Wireless Ethernet (Wi-Fi)
Fixed-Point Wireless
Cellular Telephone Networks
Wireless Connections
Satellite
 Satellite microwave
transmissions




Customer places receiving
dish in yard
Download bandwidth of
around 500 kbps
Maximum upload
bandwidth of 150kbps
Self installation makes
cost lower
http://www.ccpo.odu.edu/~arnoldo/ocean405/satellite.gif
Wireless Connections
Bluetooth
 One of the first wireless
protocols
 Operates reliably over 35
feet and can be part of up
to 10 networks of eight
devices each (personal
area networks, or PANs)
 Bandwidth of 722kbps
 Good for wireless
printing
http://www.bakercountyhealth.org/services/dental/blue-tooth.jpg
Wireless Connections
Bluetooth Advantages
 Bluetooth technology consumes very little
power
 Bluetooth devices can discover each other
and exchange information automatically
(e.g. a user can print to a printer on a
network without logging on)
Wireless Connections
Wireless Ethernet (Wi-Fi)
(802.11b)
 Most common wireless
on LANs
 Bandwidth 11Mbps at
300 feet
 A computer with a Wi-Fi
network can
communicate with a
wireless access point
(WAP) to become a part
of the network
http://www.homenethelp.com/web/diagram/images/shareing-soft-wireless.gif
Wireless Connections
Wireless Ethernet Advantages
 Wi-Fi devices can roam, i.e. shift from one
WAP to another without user intervention
 Increasingly WAPs are becoming available
in public places, e.g. airports
Wireless Connections
Wireless Ethernet Developments
 In 2002 an improved version of Wi-Fi, called 802.11a was
introduced




The 802.11a protocol can transmit at speeds up to 54Mbps
802.11a is not compatible with 802.11b
Later in 2002, the 802.11g protocol was introduced which
is compatible with 802.11b devices and has speeds of
54Mbps
In 2004-2005, 802.11n was expected (320Mbps)

In January 2006 the 802.11n proposal was confirmed and
manufacturers began supplying chips with throughput of
300Mbps - 600Mbps for sampling
Wireless Connections
Fixed Point Wireless
 Uses a system of
repeaters (transmitterreceiver devices) to
forward a radio signal
from the ISP to
customers
 Users’ antennas are
connected to a device that
converts radio signals to
Wi-Fi packets which are
sent to their computers
http://www.erinc.com/apps_wireless/images/fixed_wireless2.gif
Wireless Connections
Cellular Telephone Networks
 In 2003, about 500 million
mobile (cell) phones
existed worldwide
 Originally slow data
communication (10 kbps –
384kbps)
 Third generation cell
phones

Up to 2 Mbps
http://www.mtco.com/graphics/cellularpic.jpg
Wireless Connections
Cellular Telephone Networks Cont’d
 Cell phones send and receive messages using the
short message service (SMS) protocol
 Some cell phones (e.g. the Blackberry,
http://www.blackberry.com) include:




a Web browser which provides web access
Email
short message service (sms)
Instant messaging
Wireless Connections
Cellular Telephone Networks Cont’d
 Cell phones send and receive messages using the
short message service (SMS) protocol
 Companies also sell Internet access through their
cellular networks


Fixed fee plus charge for amount of data transferred
Business potential of mobile commerce

Companies are identifying the kinds of resources
individuals might want to access (and pay for) using
wireless devices
Electronic Commerce Software

What are some of the
software requirements
for an e-commerce
site?
Electronic Commerce Software
Cont’d

The software requirements for e-commerce
sites vary tremendously and are dependent
on several factors including:


The size of the enterprise and its projected
traffic
The budget
Electronic Commerce Software
Cont’d

All e-commerce solutions must provide at
least the following:



A catalog display
Shopping cart capabilities
Transaction processing
Electronic Commerce Software
Cont’d

Larger e-commerce sites require additional
functionality, such as:






Middleware that links the company’s existing system
(inventory control, order processing and accounting)
to the e-commerce system
Databases and Applications
Supply chain management software
Customer relationship management software
Content management software
Knowledge management software
Tools

Several tools are used in the construction of web
sites including:

HTML editors


E.g. Microsoft FrontPage, Microsoft Office and Macromedia
Dreamweaver
Other tools include:




Debuggers
HTML/XML validators
Graphic editors
Text editors
Tools (Cont’d)


These tools are useful since they allow
people with very little knowledge of
HTML to create web pages
It is important to be careful with tools,
however since the code that is
automatically generated may be difficult to
decipher if a problem does occur
References
[1] Schneider, Gary, P., “Electronic Commerce: The second wave”, Thomson Course Technology,
Fifth Annual Edition, 2004
[2] Zhao, Jensen J., “Web design and development for e-business”, Prentice Hall, 2003
[3] Federal Networking Council, “FNC Resolution: Definition of the Internet”, 1995. Online
document available at http://www.itrd.gov/fnc/Internet_res.html
[4] NetCraft, “April 2004 Web Server Survey”, 2004. Online document available at
http://news.netcraft.com/archives/2004/04/01/april_2004_web_server_survey.html
[5] Furdyk, Michael, “Ultimate Guide to Networking: Part One”, 1999. Online document
available at http://www.hardwarecentral.com/hardwarecentral/print/158/
[6] Webopedia, “Network”, 2004. Online document available at
http://networking.webopedia.com/TERM/N/network.html
[7] Berlin, Dan, et al., “CGI Programming Unleased”, Sams.net Publishing, 1996, pp. 101-102
[8] NetCraft, “April 2006 Web Server Survey”, 2006. Online document available at
http://news.netcraft.com/archives/web_server_survey.html
[9] Sybex Inc, “Networking Complete”, Sybex, Inc, Third Edition, 2002