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Chapter Two Computer Terminology & History

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1 Chapter Two Computer Terminology & History
Hardware Computer Forensics and Cyber Crime Britz

2 Hardware Input devices Camera Output devices Modems Keyboards Mouse
Scanner Camera Microphones Output devices Modems Monitor CPU Printers Computer Forensics and Cyber Crime Britz

3 Processing devices Buses CPU Motherboards PC Cards
Computer Forensics and Cyber Crime Britz

4 Modems Electronic devices which connect a computer and telephone line to enable communication between computers by converting binary data to analog tones and voltages communicable over an analog communications cable and vice versa. Computer Forensics and Cyber Crime Britz

5 Keyboards    Keyboards – devices through which commands and information are introduced to the computer hot keys – found on reconfigured keyboards – perform a multitude of tasks including system security Computer Forensics and Cyber Crime Britz

6 Mouse and Scanners Mouse - Input device which facilitates the manipulation of an onscreen cursor by hand Scanner - input device which enables users to import photographs, documents, or other sorts of paper information Computer Forensics and Cyber Crime Britz

7 Output devices           devices which produce and/or display information that has been processed by the computer for dissemination to the user Computer Forensics and Cyber Crime Britz

8 Monitors & Printers Monitor – output device originally called a CRT (Cathode Ray Tube) which communicates to users in a digestible format the results of their commands Printers – devices that create printed documents, per the computer’s instructions, to reflect the results of their commands. Computer Forensics and Cyber Crime Britz

9 Processing components
Central Processing Unit (CPU) – single integrated circuits which actually interpret program instructions and the processing of data in a computer Buses – multiple connections consisting of several parallel wires between chips and memory chips. These parallel electrical connections permit the transfer of several bits of data simultaneously. Motherboard – primary circuit board of a PC to which all other elements are connected. Such components include: processor memory chips, BIOS, and ROM. Computer Forensics and Cyber Crime Britz

10 PC Cards or PMCIA (Personal Memory Card International Association) – plug-in boards originally designed for laptops. Initially the size of a credit card, their capabilities include: hard drives, network interfaces, flash memory cards, modems, SCSI, CD-ROM and audio drives. SCSI (Small Computer Interface System) – increasing popular, SCSIs provide interfacing for up to 7 peripherals acutally, an 8-bit bus interface, but the host adapter which connects to the computer’s bus also counts as a device), and allows communication between any two devices simultaneously. Relied upon for speedy transfers, wide SCSI provides up to 40 MB/sec. Computer Forensics and Cyber Crime Britz

11 Computer Software series of instructions that performs a particular task – more specifically – the interpretation of binary byte sequences represented by a listing of instructions to the processors Computer Forensics and Cyber Crime Britz

12 Software Language Programs – the sequence of rules through which software operates Source code – the set of instructions written in programming language Object code – that which is actually executed by the computer Computer Forensics and Cyber Crime Britz

13 Malware also called malicious programming code - software which causes damage to computer systems includes trap doors, Trojans, viruses, worms, etc. Computer Forensics and Cyber Crime Britz

14 Malware Trap doors – malware which allows users to enter systems without authorization. Also called back doors, they are often installed by software developers and exploited by hackers. Trojan horses- a malware program, which on its face, appears to have a legitimate purpose, but which hides other features such as trap doors. Unlike viruses and worms, Trojans do not replicate. Computer Forensics and Cyber Crime Britz

15 Virus Virus – malware which is usually attached or inserted into a file or the boot sector of a disk. A rogue computer program which is designed to disperse copies of itself to other computers for destructive purposes by attaching itself to programs and replicating Computer Forensics and Cyber Crime Britz

16 Virus  a boot sector virus can also infect a hard drive where it is much more dangerous. introduced to computer systems as part of an infected COM, EXE, or boot sector program file, or through network downloads as macros, set-up files, or attachments continuum of destruction – range from the relatively harmless, designed to prove the superiority of its creator, to the catastrophic, shutting down entire networks never accidental in their creation – although they may be spread by unknowing victims, their creation and initial implementation are always deliberate uncontrollable – once created they are unstoppable until antidotes are discovered Computer Forensics and Cyber Crime Britz

17 Droppers Droppers – programs that are created to avoid anti-virus detection usually by encryption that hinders detection. Their typical function is to transport and install viruses when an infected computer performs a certain function. Computer Forensics and Cyber Crime Britz

18 Worms self-contained programs or sets of programs which may spread functional copies of themselves or their segments to other computer systems. Unlike viruses, they do not need to attach themselves to a host program. They are not specifically designed to erase or alter data, although their presence may cause crashes due to memory hogging. Computer Forensics and Cyber Crime Britz

19 Worms Network worms- several segments operating on different machines that use the network for several communication purposes. Once activated, these worms will scan for connections to the host network. Host computer worms – entirely contained on the computer they run on. These worms only use network connections to copy themselves to other computers—some variations include self-destructive programs. Computer Forensics and Cyber Crime Britz

20 Bombs Bombs – code built into malware as an activation mechanism. Like droppers, bombs are designed to activate when a specific action occurs. Malicious scripts or scheduling programs. time bombs – are those which are activated at a specific time on the infected system’s internal clock logic bombs – are those which are designed to activate upon a series of events (often used by disgruntled employees – i.e., designed to activate when a certain individual is fired or changed in the computer). Computer Forensics and Cyber Crime Britz

21 Logic Bombs Seeking Revenge
Computers have proven to be an effective means of retaliation for terminated employees. Unlike workplace violence, the manipulation of computer systems provides a mechanism for dismantling entire corporations, leaving individual employees unharmed. Systems manager Donald Burelson, for example, employed a logic bomb which targeted the commission records for over 60,000 independent insurance agents. This logic bomb was predicated on personnel records, and was activated when his employment status was changed in the system. (more info) Computer Forensics and Cyber Crime Britz

22 Operating System Operating system – a piece of software that runs user applications and provides an interface to the hardware. traditionally, almost all contained some version of DOS (disk operating system) multiple operating systems may be contained on one machine GUI (Graphical User Interface) – or WIMP (Windows, icons, multi-tasking, and pointing device – point and click technology Computer Forensics and Cyber Crime Britz

23 Network Language Computer Forensics and Cyber Crime Britz

24 TCP/IP TCP/IP (Transmission Control Protocol/Internet Protocol) – the suite of protocols that define the Internet – more specifically, a method of communication between programs which enables a bit-stream transfer of information. - originally designed as the standard protocol for Arpanet Computer Forensics and Cyber Crime Britz

25 IMAP v. POP IMAP (Internet Message Access Protocol) – method of accessing electronic mail or bulletin board messages that are kept on a mail server – i.e., permits a “client” program to access remote message stores as if they were local . Thus, mail can be accessed by multiple computers. POP (Post Office Protocol) –unlike IMAP, POP works best when one has only a single computer as it provides off-line access to these messages (ex. Netscape). Computer Forensics and Cyber Crime Britz

26 Network Language, Cont’d
ROUTERS – special purpose computers or software packages that handle the connection between two or more networks - analogous to switches found within telephone systems HUBS – central switching devices for communications lines in a star topology – they may add nothing to the transmission (passive hub) or may contain electronics that regenerate signals to boost strength as well as monitor activity (active hub) PACKETS – units of data exchanged between host computers further distinguished as headers and data packet switching – refers to the method used to move data around on the Internet Computer Forensics and Cyber Crime Britz

27 Network Language, Cont’d
COOKIES – a piece of information sent by a web server to a Web browser that the browser software is expected to save and to send back to the server whenever the browser makes additional requests from the server ·  stored information which is supplied by the user and placed on a hard drive to assist in online transactions and communications ·  originally designed so that users do not have to continuously supply the same information DNS entry – (Domain Name System) – based on a group of computers on a common network defined by a commonality of Internet Protocol Addresses - in a nutshell – DNS was necessary due to the explosion of the Internet – developed the .com, .gov, .org, .edu, etc.   Computer Forensics and Cyber Crime Britz

28 Hacker Language back door – a hole in security deliberately left within a program or software which enables unauthorized access Bit bucket – final destination of discarded, lost or destroyed data Black Hat hacker – term which refers to evil crackers Computer Forensics and Cyber Crime Britz

29 Hacker language, cont’d
Cracker – term originally coined by hackers which usually refers to those individuals violating secure systems for illicit purposes rather than fun. (Hackers claim to be motivated purely by intellectual pursuits, while “crackers” exploit systems for economic reasons or other forms of personal gain. Crackers are often referred to as “cyberpunks”.) Phreaking – art and science of cracking the phone network (i.e. making illegal phone calls) Red Hat hacker – tongue in cheek reference to a flavor of the Linux operating systems Sneaker – individual hired by a company to test their security systems by attempting to violate them Spaghetti or kangaroo code – complex or tangled code Computer Forensics and Cyber Crime Britz

30 Hacker Language, cont’d
 Vulcan nerve pinch – keyboard combination that forces a soft-boot or jump to ROM monitor. Many microcomputers combination is Ctrl-Alt-Del. Sometimes called the “3 finger salute.” Wedged – refers to the inability of a computer to make progress. Unlike a crash, computers which are wedged are not totally nonfunctioning. Wetware – term used to refer to humans operating computers (as opposed to hardware and software) White hat hackers – term used in the industry to designate “good” hackers Computer Forensics and Cyber Crime Britz

31 A Brief History of Computers
              

32 Computers as a concept Computer – a device used to ascertain an amount or number by calculation or reckoning  Earliest Computer – invented over 800 years ago by the Chinese - abacus Computer Forensics and Cyber Crime Britz

33 Significant Individuals and Developments
most developments occurred due to government funding Charles Babbage Herman Hollerith Professor John Atanasoff and Clifford Berry John W. Mauchly & John Presper Eckert ENIAC Professor Max Newman Computer Forensics and Cyber Crime Britz

34 Charles Babbage England – designs analytical engine in London that was designed to receive instructions from punch cards, make calculations with the aid of a memory bank and print out mathematical solutions Unprecedented ideal Failed due to lack of technological infrastructure Computer Forensics and Cyber Crime Britz

35   Herman Hollerith       United States - designed a machine to tabulate the 1890 U.S. Census Retired from civil service in 1896 to start his own company – the Tabulating Machine Company – now IBM Computer Forensics and Cyber Crime Britz

36 Professor John Atanasoff & Iowa State University student Clifford Berry
Atanasoff-Berry Computer (ABC) had capabilities which included binary arithmetic, parallel processing, separate memory, regenerative memory, and basic computer functionality. Computer Forensics and Cyber Crime Britz

37 John W. Mauchly and John Presper Eckert
University of Pennsylvania Designed for calculating firing and bombing tables for the U.S. military Computer Forensics and Cyber Crime Britz

38 ENIA (Electronic Numerical Integrator and Computer)
comprised of 30 separate units and weighed 30 tons 19,000 vacuum tubes, 150 relays, and required 200 kilowatts of electrical power to operate Computer Forensics and Cyber Crime Britz

39 Professor Max Newman (England)
develops Colossus 1 – designed exclusively for cryptanalysis Used paper tape to scan and analyze 5000 characters per second Used in WWII to break Enigma codes Computer Forensics and Cyber Crime Britz

40 Realms of the Cyberworld
Intranets – small, local networks connecting computers which are within one organization and which are controlled by a common system administrator Internets – connect several networks, and are distinguished in the literature by a lower case “i” the Internet the largest network in the world, an international connection of all types and sizes of computer systems and networks a system of small networks of computers linked with other networks via routers and software protocols Computer Forensics and Cyber Crime Britz

41 A Brief History of the Internet
1960s and 1970s - ARPANET (Advanced Research Project Agency Network) developed in 1969 by the Department of Defense to maintain lines of communication in the event of a nuclear war linked UCLA, Stanford, UC Santa Barbara, and the University of Utah April 7, 1969 – the “Internet’s official start date Characterized by non-interactive postings (i.e. RFC – Request For Comment) Opened to non-military users in the 1970s – most takers were involved with universities Extremely unfriendly to users! Computer Forensics and Cyber Crime Britz

42 1980s NSF Net – National Science Foundation
Eventually acted as a springboard for a myriad of software, including: ·  UNIX – Bell Labs ·  Eudora ( system) – Univ. of Illinois ·  Gopher (information retrieval) – U. of Minnesota Pine ( system) – U. of Washington CU-SeeMe (low cost video conferencing – Cornell Commercial Internet Xchange (CIX) - Midlevel networks were leasing data circuits from phone companies and subleasing them to institutions Emergence of domain names Computer Forensics and Cyber Crime Britz

43 Late 1980s and 1990s – World Wide Web
1989 – WWW invented by Tim Berners-Lee – a physicist working at CERN – the European Particle Physics Laboratory as a communication medium for physicists Originally text only – but the introduction of NCSA Mosaic introduced graphical interfaces Dial-up modems were granted access to Web WWW explodes in popularity 300 host computers in 1981 to over 36 million in 1998. 10-25 million users in 1991 to 157 million in 1998 Computer Forensics and Cyber Crime Britz

44 Categorizing Internet Communications
World Wide Web Newsgroups and Bulletin Boards Internet Relay Chat Computer Forensics and Cyber Crime Britz

45 World Wide Web a collection of hyperlinked pages of information distributed over the Internet via a network protocol called HTTP (hypertext transfer protocol) may be likened to an electronic marketplace where electronic storefronts of businesses, individuals, civic groups, and governments market both tangible and intangible products Variety of goals Informational Educational Transactional, etc. Each Web site can be identified by its URL (Uniform Resource Locator) Increasing exponentially – 200% yearly increases are expected Computer Forensics and Cyber Crime Britz

46 Newsgroups/Bulletin Boards
oldest and most cumbersome of all digital communications may be likened to community bulletin boards where individuals post meetings, information, etc. Bulletin Boards – a medium of computer exchange whereby individuals may have the capability of accessing software, posting personal information, and exchanging electronic mail Extremely popular among subversive organizations – it is cheaper, and the risk of exposure is significantly less Computer Forensics and Cyber Crime Britz

47 Grouping Bulletin Boards
Security Immediacy Community Computer Forensics and Cyber Crime Britz

48 Grouping Bulletin Boards
 SECURITY Anonymous – those in which true identities are unknown and handles are assigned Moderate – those in which the sysop believes he/she knows the identity of the member Known user – those in which the sysop maintains complete control over postings – prohibiting role playing and pseudonymous postings IMMEDIACY Chat lines – immediate postings (i.e., can “chat” simultaneously Stored messages – single phone line boards which store messages serially in order of their posting time Computer Forensics and Cyber Crime Britz

49 Grouping Bulletin Boards - Community
Antiseptic - those boards which serve as software or information dumps – little or no contact between users or sysops Interpersonal – boards where interaction between users is encouraged (or even demanded) these boards do NOT allow lurkers – (i.e. those individuals who do not actively engage in communication, but simply watch those who do very popular among fringe groups – hackers, Satanists, anarchists, Nazis, pedophiles, child pornographers, etc. Underground - are transient and elusive, appearing and disappearing relatively quickly Computer Forensics and Cyber Crime Britz

50 Internet Relay Chat AKA medium in which users may observe and participate in real time conversations while “identifying” the nicknames of the individuals on the channel and their corresponding internet address Topics – range from the innocuous to the profane (ex. Gardening to child exploitation) Far less expensive than telephone communications allows for multiple, simultaneous communications liked to a “technologically evolved party line” OSP’S – most chatrooms are sponsored by online service providers Unfortunately, OSP’s fail to warn customers of the potential for deception. In fact, many actually promote feelings of security by offering user vacations, fraternities, and the like. Computer Forensics and Cyber Crime Britz

51 Future Issues and Conclusions
Problems will continue to mount as LE struggles to keep up with computer criminals. New technology will continue to pose significant problems for law enforcement. Advent of cable modems (and stagnant IP’s) will increase the vulnerability of users. Computer Forensics and Cyber Crime Britz


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