ELC 200 Day 9

illnurturedtownvilleΚινητά – Ασύρματες Τεχνολογίες

21 Νοε 2013 (πριν από 3 χρόνια και 9 μήνες)

82 εμφανίσεις

Elias M. Awad


Third Edition


ELECTRONIC COMMERCE

From Vision to Fulfillment

6
-
1

© 2007 Prentice
-
Hall, Inc

ELC 200 Day 9

6
-
2

© 2007 Prentice
-
Hall, Inc

Agenda


Questions from last class?


Assignment 2 Corrected


9 A’s, 2 B’s, 6 C’s & 2 D’s


Assignment 3 Feb 25 @ 3:35 PM


Quiz 2 will be on Feb 28


Chapter’s 3, 4, 5 & 6


20 M/C @ 4 Points each


4 short essays @ 5 Points each


1 extra credit question for 5 Points


50 mins, Open Book, Open Notes


Possible Extra Credit questions


Where’s my name?


Who’s this guy? >>>




Discussion on Mobile Commerce

Hint >>>

Elias M. Awad


Third Edition


ELECTRONIC COMMERCE

From Vision to Fulfillment

6
-
3

© 2007 Prentice
-
Hall, Inc

Mobile Commerce:

The Business of Time

6
-
4

© 2007 Prentice
-
Hall, Inc

The focus of this chapter is on
several learning objectives


The basic concept of wireless commerce



The reasons for going wireless



How wireless technology is employed



Wireless (in)security



The role of cellular phones in wireless commerce

6
-
5

© 2007 Prentice
-
Hall, Inc

Learning Objectives (
Cont’d
)


Factors in designing a wireless local network



The protocols for M
-
commerce architecture



The dawn of wireless banking

6
-
6

© 2007 Prentice
-
Hall, Inc

Wireless Communication


Transmitting signals over radio waves instead of
wires


Wireless LAN (WLAN) is a standard for wireless
networking


WLAN is becoming the backbone of mobile or m
-
commerce


Wireless networks are just as effective as wired
systems

6
-
7

© 2007 Prentice
-
Hall, Inc

What is M
-
Commerce?


Transactions and payments conducted in a non
-
PC
-
based environment



The transmission of user data (e.g., e
-
mail,
spreadsheet) without wires



The management of the processes that handle the
product or service needs of a consumer via a
mobile phone



Use of wireless devices to facilitate the sale of
products and services, anytime,
anywhere

6
-
8

© 2007 Prentice
-
Hall, Inc

M
-
Commerce Categories of
Services


Information
-
based consumer services



Transaction services



Location
-
centric, personalized services that anticipate your
purchases based on your location and data stored in your
“profile”



http://www.blackberry8800.com/



http://h10010.www1.hp.com/wwpc/us/en/sm/WF04a/215348
-
215348
-
64929
-
314903
-
215381.html



http://www.palm.com/us/products/smartphones/treo750/?cre
ativeID=LFB|treo750_learn_more



http://www.apple.com/iphone/


6
-
9

© 2007 Prentice
-
Hall, Inc

History of Wireless
Communication


1895, Marconi successfully transmitted radio
waves without using wires



1940s, two
-
way car radios were installed by
police, government agencies, and utility
companies



1969, introduction of a commercial cellular radio
operation on trains running from New York City to
Washington, D.C.



1978, introduction of analog
-
based cellular
telephone services to the general public

6
-
10

© 2007 Prentice
-
Hall, Inc

Three Generations of Digital
Cellular Technology


The first generation operates in the 800
-
900 MHz
(megahertz) frequency spectrum


832 frequencies available for transmission


Lock the channel for the caller and the recipient through
the telephone company’s switch



2G started in the early 1990s


Operates between 9.6 Kbps and 14.4 Kbps in the 800
MHz and 1.9 GHz frequencies


Digital, not analog transmission


Lacks a universal system of wireless communication and
lack of the bandwidth inherent in a circuit
-
switched
network

6
-
11

© 2007 Prentice
-
Hall, Inc

Three Generations of Digital
Cellular Technology (
Cont’d
)


2.5 generation is somewhere in later stages of 2G


“always on” capability


Packet
-
switched design



3G, marks the beginning of a uniform and global worldwide
standard for cellular wireless communication, capabilities
include:


Streaming video


Two
-
way voice over IP


Internet traffic with high quality graphics and plug
-
ins for
a wireless phone


Transmission speeds of 144 Kbps for fast
-
moving mobile
wireless devices

6
-
12

© 2007 Prentice
-
Hall, Inc

Three Generations of Digital
Cellular Technology (
Cont’d
)


Future 4G technology extends 3G capacity by one
order of magnitude


http://www.wsdmag.com/Articles/ArticleID/1000
1/10001.html



http://www.time.com/time/printout/0,8816,90103
1013
-
493250,00.html



http://www.wireless
-
world
-
research.org/



http://www.wired.com/news/technology/wireles
s_special/0,2914,69032,00.html


6
-
13

© 2007 Prentice
-
Hall, Inc

Generations of Cellular Service

Generation

First

2nd

2.5G

3G

Technology

Analog

Digital

Digital

Digital

Data Transfer

Rate

Data Transfer

Is Difficult

10 kbps*

20 kbps to

144 kbps

144 kbps

to 2 Mbps

Channels

~800

~800 +

2,500

~800 +

2,500

?

Cells/ Channel

Reuse

Large/

Medium

Small/

High

Based

on 2G

?

*Sufficient for Short Message Service (SMS) and wireless Web
access using the Wireless Access Protocol (WAP) or i
-
mode

6
-
14

© 2007 Prentice
-
Hall, Inc

Key Consumer Benefits


Time and money



Anywhere functionality to stay competitive



Freedom of choice



Productivity and flexibility in coordination



Location
-
centricity


6
-
15

© 2007 Prentice
-
Hall, Inc

Mobile Product Locations

Source: U. Varshney, R. J. Vetter, and R. Kalakota. “Mobile Commerce: A new Frontier,”
Computer
, Oct.
2000, 3)

6
-
16

© 2007 Prentice
-
Hall, Inc

Wireless Application Protocol
(WAP)


Designed to deliver messages and data traffic to
mobile phones within a geographical area



Open, global, industry
-
wide mobile specifications
for wireless network architecture, application
environment, and a set of communication
protocols

6
-
17

© 2007 Prentice
-
Hall, Inc

Wi
-
Fi (Wireless Fidelity)


Industry standard that makes it possible for
hardware firms to create wireless products that
communicate with one another



Access point spreads Internet access



Makes the work environment more mobile and
easier to shift workspaces around within the firm



Security remains a major concern


Professor Gauvin’s paper on Wi
-
Fi (in)security


wireless insecurity.doc

6
-
18

© 2007 Prentice
-
Hall, Inc

Wi
-
Fi
(continued)


Offices transmit data from a company’s intranet to
employees on the move



Employees on the move can help companies
reach suppliers and improve customer service



Wireless devices in a warehouse or a
manufacturing facility can reduce handwritten
reports and missed deliveries



Wireless devices open new shortcuts to stock
trading, banking, and personal finances

6
-
19

© 2007 Prentice
-
Hall, Inc

Key Limitations


Distance



Speed



Security and privacy



Quality of service varies



Difficult for the user to remember all the phone
numbers, keywords, or codes



Batteries have a poor record

6
-
20

© 2007 Prentice
-
Hall, Inc

Key Limitations
(Cont’d)


Mobility does not matter when already overwhelmed with
information at work



Connecting charges continue to be high



For certain destinations, a GPS in your car in not that useful



Immediate response is expected



No peace anymore in public places



Poor implementation of many wireless networks

6
-
21

© 2007 Prentice
-
Hall, Inc

Critical Success Factors


Mobility



Personalization



Global standardization



Customer profiling

6
-
22

© 2007 Prentice
-
Hall, Inc

Bluetooth


Universal, low
-
cost, low
-
powered wireless
technology that uses short
-
range radio frequency
(RF) to hook up wireless connectivity among
computers, scanners, and printers


Allows any Bluetooth
-
enabled device to
communicate with other similar devices,
regardless of manufacture


Allows electronic devices to communicate and
share information without action from a user,
wires, or cables


Low complexity


Robust

6
-
23

© 2007 Prentice
-
Hall, Inc

Layered Bluetooth Architecture


Primary layer, called the
radio layer
, forms the physical
connection interface that oversees transmission within a
small network called a piconet



Second layer, is the
baseband
, which with a radio and an
antenna makes up the physical transmission component of
a Bluetooth device



Link manager protocol (LMP) is a Bluetooth layer that sets
up ongoing link management with Bluetooth devices


Piconet management


Link configuration


Security functions


Hacking of Bluetooth is called
War Nibbling
and
bluecasing


6
-
24

© 2007 Prentice
-
Hall, Inc

Personal Area Networks (PANs)


Connect Devices On or Near a Single
User’s Desk


PC, Printer, PDA, Notebook
Computer, Cellphone


Connect Devices On or Near a Single
User’s Body


Notebook Computer, Printer, PDA,
Cellphone


The Goal is Cable Elimination

6
-
25

© 2007 Prentice
-
Hall, Inc

Personal Area Networks (PANs)


There May be Multiple PANs in an Area


May overlap


Also called piconets

6
-
26

© 2007 Prentice
-
Hall, Inc

Figure 5.11: Bluetooth
Operation

File Synchronization

Client PC

Slave

Notebook

Master

Printer Slave

Printing

Cellphone

Telephone

Piconet 1

6
-
27

© 2007 Prentice
-
Hall, Inc

Figure 5.11: Bluetooth
Operation

Client PC

Notebook

Printer Slave

Printing

Call Through Company

Phone System

Cellphone

Master

Telephone Slave

Piconet 2

6
-
28

© 2007 Prentice
-
Hall, Inc

Figure 5.11: Bluetooth
Operation

File Synchronization

Client PC

Slave

Notebook

Master

Printer Slave

Printing

Call Through Company

Phone System

Cellphone

Master

Telephone Slave

Piconet 1

Piconet 2

6
-
29

© 2007 Prentice
-
Hall, Inc

Bluetooth automotive

6
-
30

© 2007 Prentice
-
Hall, Inc

Satellite Technology


“Long
-
haul” data transmission is made possible
via satellites



Repeater

in a satellite receives the signal
representing the data and “repeats” the signal to
another location

6
-
31

© 2007 Prentice
-
Hall, Inc

GEO Satellite System

2. Point
-
to
-
Point

Uplink

3.

Broadcast

Downlink

4.

Footprint

5. Earth Station A

Earth Station B

1.

Geosynchronous

Satellite

Satellite appears stationary in sky (35,785 km or 22,236 mi)

Far, so earth station needs dish antenna

6
-
32

© 2007 Prentice
-
Hall, Inc

LEO and MEO Satellite Systems

3. Small

Omnidirectional Transceiver

1. Currently Responsible LEO or MEO

2. Next Responsible

LEO or MEO

A few thousands of km or miles (Low Earth Orbit)

or tens of thousands of km (miles) (Medium Earth Orbit)

Closer than GEO, so omnidirectional transceivers can be used

User is served by a succession of satellites

6
-
33

© 2007 Prentice
-
Hall, Inc

How Cellular Works


Network of cell sites distributed over a wide area


Radio transceiver


Base station controller


Tower and antennas



Mobile telecommunications switching office (MTSO) is a
cellular switch that places calls from land
-
based telephones
to wireless customers



System identification code (SIC)



Controlled channel



Phone transmits a registration request



MTSO keeps track of the phone’s location in a database

6
-
34

© 2007 Prentice
-
Hall, Inc

How Cellular Works
(Cont’d)


MTSO finds you and your phone in the database



MTSO picks up frequency that your phone will use
in that cell



MTSO tells your phone over the control channel
which frequencies to use



When your phone and the tower switch to those
frequencies, the call is connected

6
-
35

© 2007 Prentice
-
Hall, Inc

Cellular Telephony

B

E

H

D

I

G

L

K

F

C

M

A

J

N

P

Handoff

O

PSTN

Mobile Telephone

Switching Office

1.

Automatic

Handoff Between

Cellsites O to P as

Phone Travels

Between

Cells

6
-
36

© 2007 Prentice
-
Hall, Inc

Wireless LAN (WLAN)


Uses radio waves to connect laptops and other electronic
devices to a LAN



Identical to a regular LAN, except that the devices are
wireless



Wireless network interface card (WNIC) is a card that
interfaces between the wireless device and an access point
for data or voice transmission and reception



Access point (AP) is when a wireless station sends a frame
to a server, an access point acts as a bridge that passes the
frame over the wired LAN to the server

6
-
37

© 2007 Prentice
-
Hall, Inc

Typical 802.11 Wireless LAN
Operation with Access Points

Switch

Client PC

Server

Large Wired LAN

Access

Point A

Access

Point B

UTP

Radio Link

Handoff

If mobile computer

moves to another

access point,

it switches service

to that access point

Notebook

CSMA/CA+ACK

UTP

6
-
38

© 2007 Prentice
-
Hall, Inc

Typical 802.11 Wireless LAN
Operation with Access Points

Wireless

Notebook

NIC

Access Point

Industry

Standard

Coffee

Cup

To Ethernet

Switch

Antenna

(Fan)

PC Card

Connector

6
-
39

© 2007 Prentice
-
Hall, Inc

Typical 802.11 Wireless LAN
Operation with Access Points

D
-
Link

Wireless

Access

Point

6
-
40

© 2007 Prentice
-
Hall, Inc

Linksys

Switch

With

Built
-
In

Wireless

Access
Point

Typical 802.11 Wireless LAN
Operation with Access Points

6
-
41

© 2007 Prentice
-
Hall, Inc

Typical 802.11 Wireless LAN
Operation with Access Points


The Wireless Station sends an 802.11 frame to a server via the
access point


The access point is a bridge that converts the 802.11 frame into an
802.3 Ethernet frame and sends the frame to the server

Mobile

Station

Access

Point

Ethernet

Switch

Server

802.11

Frame

802.3

Frame

6
-
42

© 2007 Prentice
-
Hall, Inc

802.11 Wireless LAN Speeds


802.11


2 Mbps (rare)




2.4 GHz band (limited in bandwidth)


802.11b


11 Mbps,




2.4 GHz







3 channels/access point


802.11a


54 Mbps,




5 GHz (> bandwidth than 2.4 GHz)




11 channels/access point


802.11g


54 Mbps,







2.4 GHz







limited bandwidth

6
-
43

© 2007 Prentice
-
Hall, Inc

Ad Hoc 802.11 Networks


Ad Hoc Mode


There is no access point.


Stations broadcast to one another directly


Not scalable but can be useful for SOHO use


NICs automatically come up in ad hoc mode

6
-
44

© 2007 Prentice
-
Hall, Inc

802.11 Security


Attackers can lurk outside your premises


In “war driving,” drive around sniffing out
unprotected wireless LANs


In “drive by hacking,” eavesdrop on
conversations or mount active attacks.

Site with 802.11 WLAN

Outside

Attacker

Doonesbury

July 21, 2002

6
-
45

© 2007 Prentice
-
Hall, Inc

Factors When Considering WLAN


Range and coverage



Throughput



Security and integrity



Cost and scalability



User costs



Standardization of WLANs

6
-
46

© 2007 Prentice
-
Hall, Inc

Wireless Security Concerns


Transmitted message must be protected all the
way to its destination host


Host system must verify or authenticate the user


Wired Equivalent Privacy (WEP) is part of Wi
-
Fi
security mechanism that makes it possible to
encrypt messages before heading for their
destination


Uses a secret key to encrypt messages


40
-
bit key is standard but vulnerable


Even the latest 128
-
bit key is not fully secure

6
-
47

© 2007 Prentice
-
Hall, Inc

Wireless Application Protocol (WAP)


Basis for the mobile Internet



Universal standard for positive wireless Internet
implementation



Adds an Internet protocol layer to the cellular
network

6
-
48

© 2007 Prentice
-
Hall, Inc


Schematic of the WAP Model

6
-
49

© 2007 Prentice
-
Hall, Inc

WAP Protocol Stack

Wireless Application

Environment (WAE)

WAP element that establishes an interoperable environment
to allow operators and service providers to build
applications and services for a large variety of wireless
platforms.

Wireless Session

Protocol (WSP)

WAP element that decides whether a network and a device
will communicate back and forth or whether data will be
transmitted straight from a network to the device.

Wireless Transaction

Protocol (WTP)

WAP layer that ensures that data flow from one location to
another efficiently based on a request/reply paradigm

Wireless Transport

Layer Security (WTLS)

WAP element that gives security to the system via
encryption, data integrity verification, and authentication
between the user and the server

Wireless Datagram

Protocol (WDP)

WAP feature that confirms easy adaptation to the WAP
technology

Network Carrier

Method (NCM)

A technology that a wireless provider uses

6
-
50

© 2007 Prentice
-
Hall, Inc

WAP Limitations


Small keypad and without a mouse



Devices have limited memory



Reliability uncertain



A period of high latency or delays before making
the connections



Security issues



Legal Issues


6
-
51

© 2007 Prentice
-
Hall, Inc

Mobile Payments Framework
and Examples

6
-
52

© 2007 Prentice
-
Hall, Inc

Trust Issues


Customers have an inherent resistance to sharing
personal or private information with technology


Trust is a psychological state involving confident
positive expectation about another person’s motive
with respect to a given exchange or a relationship
entailing risk


Gaining customer trust in m
-
commerce can be a
daunting process


To enhance trust in mobile commerce, security must
be designed into the entire mobile system


Enhancing customer familiarity with the company


Building a reputation that suggests certainty and less risk


Providing attractive rewards to attract potential customers


Maintaining company integrity


Strengthening security controls


Use external auditing

6
-
53

© 2007 Prentice
-
Hall, Inc

Managerial Issues


Evaluate corporate needs


Evaluate the wireless needs


Send out a request for proposal (RFP)


Request a demo of the proposed wireless system


Install and test the wireless system


Train employees


Provide ongoing maintenance


Most important element is the human staff


Best practice to reduce costs is to standardize
wireless devices

6
-
54

© 2007 Prentice
-
Hall, Inc

Implications for Management


M
-
commerce is long on technologies but short on
standards


M
-
commerce opens doors to new ways of doing
business


M
-
commerce will dominate areas where they have
time
-
based

and
location
-
based

value


Consider cultural and location
-
based issues


Prepare the company to offer mobile services that
will be strategically advantageous to the business


Experiment with the new m
-
technology and view
the whole effort as an investment in tomorrow’s
way of doing business

6
-
55

© 2007 Prentice
-
Hall, Inc

Chapter Summary


M
-
commerce is the transmission of user data
without wires


The wireless Web is a technological frontier, open
and growing


The main benefits are convenience, flexibility, and
efficiency with anytime, anywhere access


Wireless limitations address distance, speed, and
security factors


Four critical success factors need to be
monitored: mobility, personalization, global
standardization, and customer profiling

6
-
56

© 2007 Prentice
-
Hall, Inc

Chapter Summary (
Cont’d
)


Bluetooth is a universal, low
-
cost wireless
technology designed for short
-
range radio
hookup for wireless connections among
computers, scanners, and printers


Key layers of Bluetooth are the radio layer,
baseband layer, and link manager protocol


The transmitted message must be protected all
the way to its destination, and the host system
must verify or authenticate the user it is
communicating with


2G digital cellular technology expedites vehicles
in motion

6
-
57

© 2007 Prentice
-
Hall, Inc

Chapter Summary (
Cont’d
)


A cell site contains a radio transceiver and a base
station controller


Cell sites coordinate the hand off as you move
from one cell to another


The most common standard for wireless
networking is the WLAN


To consider WLAN technology, you must consider
range and coverage, throughput, security and
integrity, cost and stability, and standardization


Most WAP benefits are reflected in wireless
applications

6
-
58

© 2007 Prentice
-
Hall, Inc

Chapter Summary (
Cont’d
)


WAP has the limitations of low
-
power CPU, small
screens with questionable clarity, limited device
memory, small keypads and no mouse,
questionable connections for reliability, and high
latency


Companies are beginning to consider the liability
issues, as well as managerial issues