Computer Forensics and Cyber Crime PDF

Computer Forensics and Cyber Crime CHAPTER 2 Computer Terminology and...

Computer Forensics and Cyber Crime CHAPTER 2 Computer Terminology and History Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  A Brief History of Computers Calculating machines, the predecessors to computers, go back centuries. Encoding data in binary language can best use a computer's ability to process data. Computer technology evolved from vacuum tubes to solid state processors, and from inputting data using paper tape to typing it in using a graphic user interface (GUI) platform like Windows. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Language While computer hardware included the physical computer, software provided the computer program, encoded in binary language, that would process the data. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Hardware Millions of transistors, which use electricity to contain the value of 1 or 0, make up the central processing unit (CPU) an integrated circuit. Embedded in a circuit board, or motherboard, the CPU could connect to essential computer hardware. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Hardware That hardware included a PC card, or plug- in board, typically used with laptops. Wires that linked the CPU to other data sources like memory chips and buses, could also connect to:  Peripheral devices, like speakers or a modem  A universal serial bus (USB), a standardized connection of other hardware like a flash drive Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Hardware Ways to submit data for processing meant using input devices such as:  Keyboard  Modem, connected to a network  Scanner, which could take printed information to translate it into a digital format Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Hardware Places for storing data in memory could include:  ROM chips, for frequently used, permanent data  RAM chips, for the storage of data that could change Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Hardware Other mass storage devices included:  A hard drive, which can typically store very large amounts of data  Smaller, portable media like a flash or thumb drive that connects to the computer via a USB port Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Computer Software Software critical to the operation of the computer include:  Boot sequence instructions, which instruct the computer how to proceed upon powering on  An operating system, which runs user applications, such as office productivity software like Microsoft's Office Suite, and which provide the graphic user interface for the user Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Beyond DOS: Contemporary Operating Systems Microsoft Windows OS improved upon DOS by:  Adding a graphic user interface and features like Plug and Play  Creating a central registry  Upgrading to 32-bit and then 64-bit computing Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Beyond DOS: Contemporary Operating Systems Apple's OS exploited the "point and click" usability of its Macintosh hardware. Frequent upgrades expanded the capacity of Apple's computers, like using more sophisticated graphics for storage of data in folders. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Beyond DOS: Contemporary Operating Systems Newer versions used the UNIX OS as a starting point. The UNIX OS has a standard command center (or kernel), a user interface (called a shell), and tools and applications. Its stability has made it the backbone of the Internet. Free, open-source versions include LINUX and Android. Smartphones may employ a variety of operating systems, including Windows, Android, and iPhone. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Application Software Application software, like Internet Explorer or Safari, fully use the underlying capacity of an OS. Malevolent application software (or malware), such as a virus, Trojan horse, or worm, can exploit the vulnerability of an OS. Anti-virus software and firewalls can limit the undesirable use of a computer, but new malware, like droppers and logic bombs, continue to bedevil users. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  A Brief History of the Internet Begun as communication network technology, widespread use of the Internet took off with the advent of a graphic interface: a browser. Internet service providers (ISPs) would connect individual computers to the Internet, using rules of the hypertext transfer protocol to link with specific domains or locations. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Network Language Terms associated with network technology include:  Routers: Computers or software packages designed for making connections between networks  Hubs: These switching devices can, for example, pass along or potentially boost the strength of a communication  Packet: The unit of data exchanged among computers, which make it possible to send multiple communications along a data transmission line Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Network Language  Cookies: Small pieces of data, sent by a server to a browser, that typically reflect the preferences of the user, like a user's address or phone number, for the next time the user visits a site  Domain name system: Made up of a group computers that share a network that has in common Internet Protocol (IP) addresses, like those ending in.com,.net, or.org Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Network Language  Peer-to-peer networking: A network where individual computers connect, with one as the client and the other as the server, with the potential ability to preserve the anonymity of users  Cloud computing: This model defines computing as a service and not a product, which uses a system of servers for the storage of data and software via the Internet Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Realms of the Cyberworld Networked systems that make up the realms of the cyberworld include:  Intranets: Local computer networks, with access often limited to a single organization  Internets: Larger than intranets, usually consisting of several networks  The Internet: World-wide in scope, it is the biggest computer network Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved Data Bandwidth Transfer Rates Dial-up connections to the Internet measure speed of data transfer in terms of bands. Higher-speed connections, via cable, satellite, digital subscriber lines or dedicated lines, tend to measure speed in terms of megabits per second. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved  Categorizing Internet Communications The World Wide Web (www) connects Internet sites, often for commerce. Each site will have a unique identifier, a Uniform Resource Locator (URL), associated with a domain name. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved Categorizing Internet Communications Older forms of digital communication offered more cumbersome ways for users to connect. For example:  Electronic bulletin boards (BB) commonly relied on a manager to manage the posts of others. They could better mask the identity of users, since only the manager typically gathers identifying data.  Internet Relay Chat (IRC) typically involves "chat rooms" that allow for real-time exchanges, where people use nicknames associated with their corresponding IP address, which limits anonymity. Computer Forensics and Cyber Crime, 3rd ed. Copyright © 2013 by Pearson Education, Inc. Marjie T. Britz All Rights Reserved