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CYBER CRIME

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Introduction to Computing ­ CS101
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LESSON 39
CYBER CRIME
Focus of the last Lesson was on Database SW
In our final Lesson on productivity SW, we continued our discussion on data management
We found out about relational databases
We also implemented a simple relational database
Relational Databases
Databases consisting of two or more related tables are called relational databases
Each column of those tables can contain only a single type of data (contrast this with spreadsheet
columns!)
Table rows are called records; row elements are called fields
A relational database stores all its data inside tables, and nowhere else
All operations on data are done on those tables or those that are generated by table operations
Tables, tables, and nothing but tables!
RDBMS
Relational DBMS software
Examples:
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Access
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FileMaker Pro
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SQL Server
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Oracle
Classification of DBMS w.r.t. Size
Personal/Desktop/Single-user (MB-GB)
Server-based/Multi-user/Enterprise (GB-TB)
Seriously-huge databases (TB-PB-XB)
The Trouble with Relational DBs
Much of current SW development is done using the object-oriented methodology
When we want to store the object-oriented data into an RDBMS, it needs to be translated into
a form suitable for RDBMS
Then when we need to read the data back from the RDBMS, the data needs to be translated back
into an object-oriented form before use
These two processing delays, the associated processing, and time spent in writing and maintaining
the translation code are the key disadvantages of the current RDBMSes
Some Terminology
Primary Key is a field that uniquely identifies each record stored in a table
Queries are used to view, change, and analyze data. They can be used to:
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Combine data from different tables, efficiently
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Extract the exact data that is desired
Forms can be used for entering, editing, or viewing data, one record at a time
Reports are an effective, user-friendly way of presenting data. All DBMSes provide tools for
producing custom reports
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Desktop RDBMS Demo
We will create a new relational database
It will consist of two tables
We will populate those tables
We will generate a report after combining the data from the two tables
Today's Lecture:
Cyber Crime
To find out about several types of crimes that occur over cyber space (i.e. the Internet)
To familiarize ourselves with with several methods that can be used to minimize the ill effects of
those crimes
39.1 07 February 2000
Users trying to get on to the Web sites of Yahoo, couldn't!
Reason: Their servers were extremely busy!
They were experiencing a huge number of hits
The hit-rate was superior to the case when a grave incident (e.g. 9/11) occurs, and people are trying
to get info about what has happened
The only problem was that nothing of note had taken place!
What was going on?
A coordinated, distributed DoS (Denial of Service) attack was taking place
Traffic reached 1 GB/s; many times of normal!
In the weeks leading to the attack, there was a noticeable rise in the number of scans that Internet
servers were receiving
Many of these scans appeared to originate from IP addresses that traced back to Korea, Indonesia,
Taiwan, Australia
Three Phases of the DoS
1.Search
2.Arm
3.Attack
1. Search for Drones
The attackers set about acquiring the control over the computers to be used in the attack ...
by scanning ­ using e.g. Sscan SW ­ a large numbers of computers attached to the Internet
Once a computer with a weak security scheme is identified, the attackers try a break-in
Once conquered, that computer ­ called a drone ­ will be used to scan others
2. Arming the Drones
After several drones have been conquered, the DoS SW is loaded on to them
Examples: Tribal Flood Network, Trinoo, TFN2K
Like a time-bomb, that SW can be set to bring itself into action at a specified time
Alternatively, it can wait for a commencement command from the attacker
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3. The Actual Attack
At the pre-specified time or on command, the SW implanted on all of the drones wakes-up and
starts sending a huge number of messages to the targeted servers
Responding to those messages overburdens the targeted servers and they become unable to perform
their normal functions
Neutralizing the Attack
The engineers responsible for monitoring the traffic on the Yahoo Web sites quickly identified the
key characteristics of the packets originating from those drones
Then they setup filters that blocked all those packets
It took them around 3 hours to identify and block most of the hostile packets
BTW, the sender's IP address can be spoofed, making it impossible to block the attack just by
blocking the IP addresses
The Aftermath
None of the Yahoo computers got broken-into; The attackers never intended to do that
None of the user data (eMail, credit card numbers, etc.) was compromised
Ill-effects:
­  Yahoo lost a few million's worth of business
­  Millions of her customers got annoyed as they could not access their eMail and other info from the
Yahoo Web sites
Who Done It?
The DoS SW is not custom SW, and can be downloaded from the Internet. Therefore, it is difficult
to track the person who launched the attack by analyzing that SW
After installing the DoS SW on the drones, setting the target computer and time, the attackers
carefully wipe away any info on the drone that can be used to track them down
End result: Almost impossible to track and punish clever attackers
How to stop DoS attacks from taking place?
Design SW that monitors incoming packets, and on noticing a sudden increase in the number of
similar packets, blocks them
Convince system administrators all over the world to secure their servers in such a way that they
cannot be used as drones
BTW, the same type of attack brought down the CNN, Buy, eBay, Amazon Web sites the very next
day of the Yahoo attack
39.2 DoS Attack: A Cyber Crime
DoS is a crime, but of a new type - made possible by the existence of the Internet
A new type of policing and legal system is required to tackle such crimes and their perpetrators
Internet does not know any geographical boundaries, therefore jurisdiction is a key issue when
prosecuting the cyber-criminal
Cyber crime can be used to ...
Damage a home computer
Bring down a business
Weaken the telecom, financial, or even defense-related systems of a country
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Cyberwar!
In 1997, blackouts hit New York City, Los Angeles
The 911 (emergency help) service of Chicago was shut down
A US Navy warship came under the control of a group of hackers
What was happening? A cyber attack!
All of the above did not happen in reality, but in a realistic simulation
The US National Security Agency hired 35 hackers to attack the DoD's 40,000 computer networks
By the end of the exercise, the hackers had gained root-level (the highest-level!) access to at least 3
dozen among those networks
Cyberwarfare:
A clear and present threat as well opportunity for all of the world's armed force!
39.3 More cybercrimes ...
Mail Bombing
Similar in some ways to a DoS attack
A stream of large-sized eMails are sent to an address, overloading the destination account
This can potentially shut-down a poorly-designed eMail system or tie up the telecom channel for
long periods
Defense: eMail filtering
Break-Ins
Hackers are always trying to break-in into Internet-connected computers to steal info or plant
malicious programs
Defense: Intrusion detectors
Credit Card Fraud
A thief somehow breaks into an eCommerce server and gets hold of credit numbers and related
info
The thief then uses that info to order stuff on the Internet
Alternatively, the thief may auction the credit card info on certain Web sites setup just for that
purpose
Defense: Use single-use credit card numbers for your Internet transactions
Software Piracy
Using a piece of SW without the author's permission or employing it for uses not allowed by the
author is SW piracy
For whatever reason, many computer users do not consider it to be a serious crime, but it is!
Only the large rings of illegal SW distributors are ever caught and brought to justice
Defense: Various authentication schemes. They, however, are seldom used as they generally
annoy the genuine users
Industrial Espionage
Spies of one business monitoring the network traffic of their competitors
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They are generally looking for info on future products, marketing strategies, and even financial
info
Defense: Private networks, encryption, network sniffers
Web Store Spoofing
A fake Web store (e.g. an online bookstore) is built
Customers somehow find that Web site and place their orders, giving away their credit card info in
the process
The collected credit card info is either auctioned on the Web or used to buy goods and services on
the Web
39.4 Viruses
Self-replicating SW that eludes detection and is designed to attach itself to other files
Infects files on a computers through:
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Floppy disks, CD-ROMs, or other storage media
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The Internet or other networks
Viruses cause tens of billions of dollars of damage each year
One such incident in 2001 ­ the LoveBug virus ­ had an estimated cleanup/lost productivity cost of
US$8.75 billion
The first virus that spread world-wide was the Brain virus, and was allegedly designed by someone
in Lahore
One Way of Classifying Viruses
Malicious
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The type that grabs most headlines
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May destroy or broadcast private data
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May clog-up the communication channels
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May tie-up the uP to stop it from doing useful work
Neutral
­  May display an annoying, but harmless message
Helpful
­  May hop from one computer to another while searching for and destroying malicious viruses
Anatomy of a Virus
A virus consists of 2 parts:
Transmission mechanism
Payload
Transmission Mechanism
Viruses attach themselves to other computer programs or data files (termed as hosts)
They move from one computer to another with the hosts and spring into action when the host is
executed or opened
Payload
The part of the virus that generally consists of malicious computer instructions
The part generally has two further components:
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Infection propagation component:
This component transfers the virus to other files residing on the computer
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Actual destructive component:
This component destroys data or performs or other harmful operations
Commonsense Guidelines
Download SW from trusted sites only
Do not open attachments of unsolicited eMails
Use floppy disks and CDROMs that have been used in trusted computers only
When transferring files from your computer to another, use the write-protection notches
Stay away from pirated SW
Regularly back your data up
Install Antivirus SW; keep it and its virus definitions updated
Antivirus SW
Designed for detecting viruses & inoculating
Continuously monitors a computer for known viruses and for other tell-tale signs like:
­  Most ­ but, unfortunately not all ­ viruses increase the size of the file they infect
­  Hard disk reformatting commands
­  Rewriting of the boot sector of a hard disk
The moment it detects an infected file, it can automatically inoculate it, or failing that, erase it
39.5 Other Virus-Like Programs
There are other computer programs that are similar to viruses in some ways but different in some
others
Three types:
­  Trojan horses
­  Logic- or time-bombs
­  Worms
Trojan Horses
Unlike viruses, they are stand-alone programs
The look like what they are not
They appear to be something interesting and harmless (e.g. a game) but when they are executed,
destruction results
Logic- or Time-Bombs
It executes its payload when a predetermined event occurs
Example events:
A particular word or phrase is typed
­  A particular date or time is reached
Worms
Harmless in the sense that they only make copies of themselves on the infected computer
Harmful in the sense that it can use up available computer resources (i.e. memory, storage,
processing), making it slow or even completely useless
Designing, writing, or propagating malicious code or participating in any of the fore-mentioned
activities can result in criminal prosecution, which in turn, may lead to jail terms and fines!
Today's Lecture:
We found out about several types of computer crimes that occur over cyber space
We familiarized ourselves with with several methods that can be used to minimize the ill effects of
these crimes
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Next Lecture' Goals
(Social Implications of Computing)
We will explore the impact of computing on:
Business
Work
Living
Health
Education
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Table of Contents:
  1. INTRODUCTION
  2. EVOLUTION OF COMPUTING
  3. World Wide Web, Web’s structure, genesis, its evolution
  4. Types of Computers, Components, Parts of Computers
  5. List of Parts of Computers
  6. Develop your Personal Web Page: HTML
  7. Microprocessor, Bus interface unit, Data & instruction cache memory, ALU
  8. Number systems, binary numbers, NOT, AND, OR and XOR logic operations
  9. structure of HTML tags, types of lists in web development
  10. COMPUTER SOFTWARE: Operating Systems, Device Drivers, Trialware
  11. Operating System: functions, components, types of operating systems
  12. Forms on Web pages, Components of Forms, building interactive Forms
  13. APPLICATION SOFTWARE: Scientific, engineering, graphics, Business, Productivity, Entertainment, Educational Software
  14. WORD PROCESSING: Common functions of word processors, desktop publishing
  15. Interactivity to Forms, JavaScript, server-side scripts
  16. ALGORITHMS
  17. ALGORITHMS: Pseudo code, Flowcharts
  18. JavaScript and client-side scripting, objects in JavaScript
  19. Low, High-Level, interpreted, compiled, structured & object-oriented programming languages
  20. Software Design and Development Methodologies
  21. DATA TYPES & OPERATORS
  22. SPREADSHEETS
  23. FLOW CONTROL & LOOPS
  24. DESIGN HEURISTICS. Rule of thumb learned through trial & error
  25. WEB DESIGN FOR USABILITY
  26. ARRAYS
  27. COMPUTER NETWORKS: types of networks, networking topologies and protocols
  28. THE INTERNET
  29. Variables: Local and Global Variables
  30. Internet Services: FTP, Telnet, Web, eMail, Instant messaging, VoIP
  31. DEVELOPING PRESENTATIONS: Effective Multimedia Presentations
  32. Event Handlers
  33. GRAPHICS & ANIMATION
  34. INTELLIGENT SYSTEMS: techniques for designing Artificial Intelligent Systems
  35. Mathematical Functions in JavaScript
  36. DATA MANAGEMENT
  37. DATABASE SOFTWARE: Data Security, Data Integrity, Integrity, Accessibility, DBMS
  38. String Manipulations:
  39. CYBER CRIME
  40. Social Implications of Computing
  41. IMAGES & ANIMATION
  42. THE COMPUTING PROFESSION
  43. THE FUTURE OF COMPUTING
  44. PROGRAMMING METHODOLOGY
  45. REVIEW & WRAP-UP of Introduction to Computing