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THE INTERNET & E-COMMERCE
IS 340
BY
CHANDRA S. AMARAVADI
1
PRESENTATION OVERVIEW
 Background
 Architecture
 Protocols
TCP/IP
 HTTP and HTML
 Browser & web search
 Security
 Electronic commerce
2
BACKGROUND
 Started
as a research network
 Released into public domain in 1993
 Web technology (web pages) in 1992
 Publicly owned (Lucent, Pac Bell etc.)
 Costs borne by ISPs & industry
 200 million users on the web world wide
3
INTERNET
ARCHITECTURE
4
BASIC ARCH. CONCEPTS
Packetizing
 IP addresses
 Bridges and routers
 Root servers
 Hi-speed back bone

5
PACKETIZING DATA
Document
….
Packet 1
Packet 2
6
IP ADDRESSING
NODE
NODE
NODE (143.43.78.84)
NODE (153.54.56.82)
7
BRIDGES AND ROUTERS
143.43.78.84
Network
Bridge
Gateway
Network
143.43.78.84
Network
Network
Router
143.43.78.84
Network
153.54.56.82
8
ROOT SERVER (DNS)
NODE
ROOT SERVER
ROOT SERVER
NODE
A root/DNS server provides address information to gateways
9
BASIC ARCH. CONCEPTS..
HIGH SPEED BACKBONE
NAP
Regional
hub
Regional
network
10
ARCHITECTURE
The Internet is a network of networks
 50,000
world wide
 29,000 in USA
 16 million hosts
WWW - A network of webservers (content in
HTML) -- 3.6 million web sites
11
ARCHITECTURE

Millions of hosts connected
 Physical
connection is a bridge (hub)
 Each “host” has a unique IP address
 Hosts can be PCs, Web servers, Mainframes
Use uniform protocols (TCP/IP)
 Data is sent as packets
 Addressed by hosts
 Routed by routers

12
ARCHITECTURE
Bridges, routers, gateways
maintain directories, move data
Internet
13
ARCHITECTURE
WEB SITES
 Browsers
(terminals that access the web site -called clients)
 A web server (a special computer or minicomputer that will host the site)
 Server software (to run TCP/IP protocols)
 Web content i.e. the web page
 Firewall (mechanisms (HW/SW) for security)
14
SERVER ARCHITECTURE (FYI)
FTP
DNS
CLIENT
ACCESS
AUTHORING
TOOLS
NETWORK OPERATING SYSTEM
SERVER BOX
INTERNET INTERFACE/FIREWALL
INTERNET SERVICE PROVIDER
15
ISP ARCHITECTURE
Backbone
VBNS -- Very High Speed Backbone
Network
Access Pts. PacBell
Internet
Access
Sprint
Local
Access
Local
Provider
End
Users
Home Users
MCI
Verizon
Local
Local
Provider Provider
Small Bus.
Lucent
Lucent
Ameritech
AOL
Local
Provider
Large Bus.
UUnet
PSI
Local
Provider
Govt.
16
INTERNET PROTOCOLS
17
A HIERARCHY OF PROTOCOLS
Application
Host level
Gateway level
Network level
+
+
+
+
FTP, Telnet, HTTP
TCP
IP
FDDI, Ethernet, Token ring,
CSMA/CD ,X.25, ISDN
18
A HIERARCHY OF PROTOCOLS
(CSMA/CD)
(FDDI)
BROWSER
(HTTP)
(Ethernet)
HOST
HOST
(TCP/IP)
(TCP/IP)
WEB SERVER
(HTTP)
19
TCP/IP PROTOCOL
Protocol for reliable data transfer
A collection of 100 protocols
Hardware independent
Data is packetized
Rules for
formatting messages
establishing sessions
governing transmissions
Application
Host
Gateway
Network access
20
Source Port
D estination Port
Sequence #
Acknow ledgem ent #
Parity
O ptions
D ata
Port#, seq#, parity,...
message
Document
….
Packet 2
Packet 1
HTTP
TCP
21
INTERNET PROTOCOL (IP)
A protocol for assigning & resolving IP addresses
 Unique
address.
 Assigned by IETF/ICANN.
 In the form of a domain name (ibm.com).
 Email addresses based on this (konsynski@emory.edu)
 Translated to “dotted quad”:203.48.54.28.
What are some common domain extensions?
22
A HIERARCHY OF PROTOCOLS
(CSMA/CD)
(FDDI)
BROWSER
(HTTP)
(Ethernet)
HOST
HOST
(TCP/IP)
(TCP/IP)
WEB SERVER
(HTTP)
23
HTTP – Hypertext Transport Protocol




A protocol for formatting and transferring multimedia objects, text, etc.
“Stateless protocol”
Data is sent as plain character text
Rules specify both request and response format
24
HTTP – Hypertext Transport Protocol
(FYI)
REQUEST
GET
ACCEPT
USER AGENT
CONNECTION
Myfile.htm http/1.0
image, bitmap, JPG
Netscape 9.0
Keep alive
25
HTTP – Hypertext Transport Protocol
(FYI)
RESPONSE
Http/2.0:
OK
Server:
Netscape
Last modified: 3/9/08
Content length: 10 KB
26
HYPERTEXT MARKUP
LANGUAGE
27
HTML – HYPERTEXT MARKUP
LANGUAGE…




A tagging language based on SGML
Text appearance and structure is governed by
embedded commands or tags.
Example bold, paragraph etc.
There’s a start tag and end tag (e.g. <B>Text to be
bolded </B>)
28
HTML – HYPERTEXT MARKUP
LANGUAGE
THREE MAJOR TYPES OF TAGS
Structuring tags -- e.g. heading, body, frame etc.
Formatting tags -- e.g. bold, italic, font etc.
Hyperlink tags -- e.g. image, sound etc.
29
STRUCTURING TAGS
<HTML>
.
.
.
To begin & end HTML
.
</HTML>
30
STRUCTURING
Heading
Window title
<Head>
<title>
Main page of spectrum
</title>
</Head>
Web page heading
<H1>
……………………………
</H1>
<H2>
…………………………..
</H2>
31
STRUCTURING
Body
<Body>
.
.
Main part of web page
</Body>
<Body Bgcolor= “color” text=“color”
link=“color” vlink=“color”
alink= “color”>
32
FORMATTING
Font
<font size= “number”
face= “font name”>
color= “color”
Size = “+1”
“+2”
33
FORMATTING
Paragraph
<P> ……………. </P>
Alignment
<P align = “Left”>
_______________
_______________
_______________
</P>
Aligns left
Bold
Italic
Line Breaks
<B> …………. </B>
<I>…………... </I>
<BR>
34
HYPERLINKS
URL: Uniform Resource Locator, address of a resource
on the internet; resource could be??
<a href = “URL of page” > text or image for user
to click on </a>
e.g.
<a href = http://www.cnn.com> CNN </a>
<a href = “http://www.faculty.wiu.edu/C-Amaravadi/”> Course web sites </a>
35
IMAGES & HYPERLINKS
Image
<img src = “URL of image” height = “number”
width = “number”>
height
width
For text wrap add ALIGN = “Left”
36
HTML – HYPERTEXT MARKUP
LANGUAGE
<HTML>
<HEAD>
<!-- Title and main heading -->
<TITLE> Main Menu </TITLE>
</HEAD>
<!-- Begin body-->
<BODY BGCOLOR = “#FFFF6B” TEXT = “#A50063>
<P> <IMG SRC=“logo.jpg” height = 100 width = 600>
</P>
</HTML>
37
HTML – HYPERTEXT MARKUP
LANGUAGE
<B> ABOUT US </B> <BR>
Founded in 2006, our corporate mission.......
<SPACER TYPE = HORIZONTAL SIZE = 20>
Varyti Broadcasts -- TV Program Division
....................
</BODY>
</HTML>
38
BROWERS & EXTENSIONS
39
BROWSERS
Software to view web pages e.g. Internet
Explorer, Firefox.
Functions:
 Connection & data transfer
request connection by sending HTTP request
Respond to HTTP
receive response and displays information
 Display web pages
 Create web pages
40
WEB TECHNOLOGIES
 Plug-ins
 Java
 JSP (Java Server Pages)
 Servlets
Programs that work with
browser, e.g. audio & video
players.
programming language to
build web applications.
used to create dynamic
html pages.
compiled JSP to respond
to http requests.
41
WEB SEARCH TOOLS/ENGINES



Enable web search (look for keywords)
Store keywords & web locations
Use indexing
 Google
 Yahoo
 Answers.com
42
INTERNET
SECURITY
43
INTERNET SECURITY
Firewall -- a system designed to protect a web-site
from unauthorized access
Principles are:
 Packet
filtering
 protected host (bastion host)
 dedicated routers/switches
 monitoring and logging of users
Internet
44
E-COMMERCE
45
WHAT IS E-COMMERCE?
• Business conducted on the web
• Buyers and sellers interact electronically
Products/Services
BUYER
Online
Transactions
Payments
What is M-commerce?
SELLER

Cust to business (B2C)
◦ ordering products, books, sw, music, consumer products
◦ services, banking & finance, stock trades

Business to Business (B2B)
◦ supply of raw materials

Intra-Org
◦ inventory ordering & charge out, etc.
◦ helpdesk, etc.




Retail e.g. books, toys etc.
Premium content e.g. CNN & financial
companies
Auctions e.g. cars, steel, power
Gateways, search engines
DISCUSSION
What are the pros & cons of e-commerce? (to customers
and to businesses)
E-COMMERCE MODEL
Product Search
Comparison shopping
Placement of order
Payment information
Payment authorization
Receive merchandise
Service and support
E-COMMERCE ARCHITECTURE
Incoming Internet request
Web Server layer
Web Server
Middle-tier layer
E Commerce
Sever
Database
Backend layer
ERP System
Mainframe
ECOMMERCE ISSUES
 Volatility of information -- updates
 Ensuring adequate security
 Ethical usage of customer information
 Advertising
 Legal issues – sales, contracts etc.
That’s All
Folks!
53
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