Computer Networks Network: A connected system of objects or people Computer network: A collection of computers and other hardware devices connected together so users can share hardware, software, and data, and electronically communicate The Internet: Largest computer network in the world ae. creme Tory ccomnecrion fl) x. reer SHARED PROTER rows Pc Wired ys. Wireless Networks Wired: A network in which computers and other devices are physically connected to the network with cables ¢ Wireless: A network in which computers and other devices are connected to the network without physical cables Network Topologies: Indicate how the devices in the network are arranged * Star Networks: All networked devices connect to a central device/server * Bus Network: Uses a central cable to which all network devices connect ¢ Mesh network: Multiple connections among the devices on the network so that messages can take any of several possible paths 22i a on a 50 weTwonKs Use a sg cnr cate a comect ach corer sine STAR NETWORKS ee acon device to connec ach device act) Pe rete, Network Architectures * Client-Server Networks o Client: Computer or other device on the network that requests and utilizes network resources © Server: Computer dedicated to processing client requests ‘THE INTERNET ‘CUIENT cuENT NETWORK SERVER (provides cent devices with network servces, such as fle, nt, mai, an itermet access) 23* Peer-to-Peer (P2P) Networks © Central server is not used © All computers on the network work at the same functional level Network Size and Coverage Area ¢ Personal Area Networks (PANs): Connect an individual’s personal devices Local Area Networks (LANs): Connect devices located in a small geographic area © Metropolitan Area Networks (MANs): Cover a metropolitan area such as a city or county ¢ Wide Area Networks (WANs): Cover a large geographic area, Two or more LANs connected together Intranets and Extranets © Intranet: Private network designed to be used by an organizations’ employees; set up like the Internet © Extranet: Company network accessible by authorized outsiders Communications Protocols and Networking Standards © Protocol: © Asset of rules for a particular situation © Communications Protocol: A set of rules that determine how devices on a network communicate * Standard © A set of criteria or requirements approved by a recognized standards organization © Address how networked computers connect/communicate © Needed to ensure products can work with other products « TCP/IP: Most widely used communications protocol, Consists of two protocols © Transmission Control Protocols (TCP): Responsible for delivery of data © Internet Protocols (IP): Provides addresses and routing information, are numeric and unique, used to identify computers and devices on networks (207.46.197.32) Tw ansecuess | Toc JrScu.0d S| =. z 24© HTTP (Hypertext Transfer Protocol) and HTTPS (Secure Hypertext Transfer Protocol): Used to display Web pages ¢ FTP (File Transfer Protocol): Used to transfer files over the Internet SMTP (Simple Mail Transfer Protocol and POP3 (Post Office Protocol): Used to deliver e-mail over the Internet Ethernet: Most widely used standard for wired networks, typically used with LANs that have a star topology Wi-Fi: Current standard for wireless networks in homes and offices (wireless Ethernet), Designed for medium-range transmission WIMAX: Standards for longer range wireless networking connections, typically MANs Bluetooth: Networking standard for very short-range wireless connections Wireless USB: Wireless version of USB designed to connect peripheral devices Networking Hardware * Network Adapter: © Used to connect a computer to a network © Also called network interface card (NIC) when in the form of an expansion card * Modem: Device that enables a computer to communicate over analog networking mediaSwitch: Central device that connects devices in a wired network but only sends data to the intended recipient Router: Connects multiple networks: two LANs, two WANS, LAN and the Internet Wireless Access Point: Device used to grant network access to wireless client devices Wireless Router: Typically connects both wired and wireless devices to a network and to connect the network to the Internet Bridge: Used to connect two LANs together Repeaters: Amplify signals along a network Wired devices can connect here ede proving tere! acess : ‘comers here A wired itera Aviredéevce —-AUSB 3G0r46 SB devices uch asa print connection canconnect modem connects ‘eral hard ve) can coonect connects hee here here here TRAVEL WIRELESS ROUTERS MOBILE BROADBAND “Thi 802.1 t/bgm rater ROUTERS CONVENTIONAL WIRELESS ROUTERS gables mp devas fo ‘This 36/4 enables matiple Tis 80211 rater also inches 2 share a single wired iteret devices to share a obie ‘wich and wireless access point broadband comecton. ‘=p | 26The Internet and the World Wide Web Information and Communication Technology (ICT): The set of tools used to store, transmit, managing, processing, and representing information using computer technology Internet: Largest and most well-known computer network, linking millions of computers all over the world The World Wide Web: © The collection of Web pages available through the Internet * Web 2.0: Wide variety of content available via Web pages today such as social networking, RSS, podcasts, blogs and wikis * The World Wide Web and the Internet are not owned by any person, business, or organization The Internet Community Today ¢ Users: People who use the Internet Internet Service Providers (ISPs): Is a company that Provide access to the Internet, typically for a fee ¢ Internet Content Providers: Persons or organizations that provide Internet content o Businesses, non-profit organizations, educational institutions, individuals Application Service Providers (ASPs) and Web Services: Companies that manage and distribute Web-based software services over the Internet o Cloud software, Software as a Service (SaaS), cloudware pes of Connection and Internet Access © Dial-up connection: Use standard phone lines © Uses modem to dial-up ISP © Slower, but cheaper * Direct connection: © Device is continually connected to the Internet © Direct connections are typically broadband © Because you are always c it is important to protect your computer from hackers © Conventional Dial-Up: Uses dial-up modem connected to standard telephone jack «Cable: Most widely used home broadband connection * DSL: Broadband delivered over telephone lines * Mobile Wireless: Access via a smartphone or media tablet 7Web Browser: Is a software application for accessing information on the World Wide Web such as Google Chrome, Mozilla Firefox and Apple Safari Uniform Resource Locators (URLs): Is a text address that uniquely identifies a web page on the Internet Web page URLs usa bein This partof the URL Next comes the folders) Tis ithe Web page with http:/! (for nonsecure identifies the Web server in which the Web page & document that is to be Web gages) or haps or secure hosting the Webpage stored, necessary. rire and played Web pages) Goad nrca CD Web Site: Is simply data which is stored on a WWW server and which can be freely accessed by people Hyperlink: Is a piece of text, an object or a graphic that acts like a button Search Sites (Search Engine): Web sites designed to help users search for Web pages that match specified keywords or selected categories (Google, Yahoo) Keyword Search: Keywords are typed in a search box to locate information on the Internet Beyond Browsing and E-Mail: Many types of other online communications methods exist Instant Messaging (IM): Exchanging real-time messages Short Message Service (SMS): Used by mobile phone users ¢ Forums: Web page that enables individuals to post messages on a particular topic for others to read and respond to © Voice over Internet Protocol (VoIP): Making telephone calls over the Internet (Skype) © Web Conference: Face-to-face meeting (videoconferencing) taking place via the Internet Webinar: A seminar presented via the Web © Webcast: A completely one-way presentation © Social Networking Sit site that enables a community of individuals to communicate and share information 28« Social Media: The collection of social networking sites and other communications channels used to share information (Facebook) Online Shopping and Investing Online Shopping: Buying products or services over the Internet Online Auction: Bids are placed for items and the highest bidder purchases the item Performing banking activities via the Web : Buying and selling stocks or other types of investments via the Web Online Music: Music played or obtained via the Web Online TV, Videos, and Movies: Videos watched or downloaded via the Web Online News: Available through Web sites belonging to news organizations, television networks, newspapers, magazines, ete « RSS (Really Simple Syndication) Feeds: News tool that delivers selected Web content to subscribers as the content is published to a Web site © Podcasts: Recorded audio or video file that can be played or downloaded via the Web Online Education: Using the Internet to facilitate learning * Web-based learning management systems (LMS): Used to deliver course content, manage assignments and grades, and more * Distance Learning: Students take classes from a different location from the one where the delivery of instruction takes place © Online Testing: Taking tests via the Internet, Online Writing © Blogs: A Web page that contains short, frequently updated entries in chronological order, typically by just one individual © Wikis: A collaborative Web page that is designed to be edited and republished by a variety of individuals © E-portfolios: A collection of an individual’s work accessible via the Web 29