Transcript Chapters 1-8 notes - SRU Computer Science

Chapter 1: E-commerce Growth
Internet Growth Study of 2000 companies
By 2002, over a trillion dollars in revenue
Billions of
dollars 600
500
400
Internet Co.
E-commerce
300
200
100
0
1998
1999
E-business & E-commerce
 Revolutionize conventional business
models
Transition from brick and mortar
Personalize user’s experience
Privacy Invasion
Multimedia and e-commerce packaged
Intro to Computers 
 Hardware
– Input, output, memory
– ALU, CPU, storage
 Languages
– Machine
– Assembly
– High level
 Structured
Programming
 Internet History
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60’s ARPAnet
TCP/IP
DARPA
Csnet
80’s Internet
90’s WWW
Internet Software you
should know
will learn
 Browsers
– IE, Netscape
 E-mail
 Chat
 ftp
HTML
Javascript
DHTML
VBscript
XML
ASP
Chapter 3: e-Business
A company that has a online presence
 Storefront model
– Shopping cart technology
-- amazon.com
– Shopping mall – mall.com
 Auction model – liquidprice.com, ebay.com
 Dynamic pricing model
– Name your price – priceline.com
– Comparison Pricing – Bottomdollar.com
– Demand Sensitive Pricing – www.mercata.com
– Bartering, rebates, free products and services
 Portal model – hotbot.com
E-businesses
 Business to
business (B2B)
– Buying, selling,
partnering,
bartering, trading
 Online trading and
lending
 Getting loans
 Recruiting
 News
 Travel
 Entertainment
 Automotive
 Energy
 Selling Brain
Power
 Art
 E-learning
Chapter 4 – Internet Marketing
5 – Online Monetary Transacts
 Advertising on the
web
 Choosing a domain
name
 ….
 Take Dr. Orvis’
course, not mine 
Chapter 6 – Legal, Ethical and
Social Issues; Internet Taxation
Right to Privacy
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Cookies
Tracking devices
Employer/Employee
User protection:
PrivacyX.com
– Business protection:
PrivacyBot.com
Legal Issues
– Defamation of char
– Sexually explicit
speech
– Children (netnanny)
– Intellectual Property
– Copyright Issues
mp3, napster…
Social Issues; Internet Taxation
Trademarks
Domain Registration
Unsolicited
Social Issues
Online communities
Activism
disabilities
commercial e-mail
Global Issues
(SPAM
Online Auctions
Taxation
Online Contracts
Chapter 7: Computer and
Network Security
Secure Transactions
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Privacy: captured or passed on
Integrity: altered
Authentication: prove identities
Non-repudiation: prove message sent or
received
Cryptography
 Transform data using a key
 Plaintext: Unencrypted
 Ciphertext: encrypted data
 Cipher or cryptosystem – encryption algo.
 Substitution cipher
 Transposition cipher
 The longer the key (128 bits), the stronger the
encryption
Secret key cryptography
symmetric cryptography
 Both sender and receiver need to know key
 How do you send the key securely?
– Courier
 Key distribution center (KDC)
– Session key generated
– Sent to merchant and customer
– Using key already held
 Data Encryption Standard (DES)
– 64 bit key example of symmetric crypto
 Triple DES
Public key cryptography
Asymmetric cryptography
 Two inversely related keys
– Private key: kept secret by owner
– Public key: freely distributed
 Cannot deduce private key from public
 Sender encrypts using receiver’s public key
 Receiver decrypts using receiver’s private key
 Keys are mathematically related
 Computational intensive
Symmetric vs. Asymmetric
cryptography
 Asymmetric not efficient for large amounts of
data
 Use public key to determine key for symmetric
encryption on insecure medium
 Key agreement protocol
– Process by which two parties can exchange keys over
insecure medium
– Protocol sets the rules for communication
 Digital Envelope
– Message encrypted using symmetric secret key
– Sym secret key encrypted using public-key encrypt
– Sends both as one message
Security Protocols
 Secure Sockets Layer (SSL)
– Netscape; secure communication on web
– Public key technology and digital certificates
– Does not protect private info like credit cards
 Secure Electronic Transaction (SET)
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Protocol developed by Visa and MasterCard
Digital certificates to authenticate
Public key
Merchant never sees credit card info
Security Attacks
 Denial of service
– Disrupt service, attack routing tables
– Network resources taken up by unauthorized users
 Viruses
– Attached to other programs
– Replicates, corrupts files
– Melissa and ILOVEYOU
 Worms
– Like viruses but do not need to be attached
Viruses
 Hackers
 Transient virus
– Attaches to specific program. Live during execution
 Logic bomb and time bomb
– Triggers when given condition met
 Trojan horse
– Hides in friendly program
 Web defacing
– Enter Web site and change contents
Network Security
 Firewalls
– Protect LAN from outside
 Packet filtering firewall
– Filters packets from outside with local addresses
– Does not examine data  viruses
 Application-level gateway
– Screen actual data
– Firewalls
 Kerberos
– MIT, symmetric secret key, internal attacks
– Ticket Granting Service maintains DB of valid users
Chapter 8: Hardware, Software
and Communications
 Internet Structure
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Host computers with IP address
Packets with source address, destination address,
sequencing information, error-control information
– Routers: move packets efficiently. Failures.
 Hardware
– Server: Web, e-mail, database, file
– Client
– Communication Media:Wire, fiber, satellite,
microwave, repeater
– Storage Area Networks (SANs): high-capacity
data delivery and storage on a network
Connecting to the Internet
 Internet Service Provider (ISP)
– Analog to digital (modem)
 Digital Subscriber Lines (DSL)
– High bandwidth of existing copper (upto 55Mbps)
– Special HW at phone co; speed decrease over distance
 Broadband
– High bandwidth provided by cable TV and tele co.
– Cable modem (downstream 384Kbps –1.5Mbps)
 Integrated Services Digital Network(ISDN)
– High-speed connections (128Kbps)
– Need Terminal Adaptor (TA) and ISP  $$
 Wireless: Cell phones, palms
 WebTV: Connect TV to ISP
Software
 Application Service Providers (ASPs)
– Maintain application and update as needed
– Provide Virtual Private Networks (VPNs)
– Point-to-point tunneling protocol (PPTP)
 Operating Systems (OS)
– Linux
 Databases (DB)
– Relational
– DBMS
– SQL