Itec 1010 Information and Organizations F2024 PDF

ITEC 1010 Information and Organizations F2024, Section A Ch 4: Telecommunications and Networks ©© 2024 2022 Pavlovych Pavlovych ©© 2018 2018 CENGAGE, CENGAGE, ALL ALL RIGHTS...

ITEC 1010 Information and Organizations F2024, Section A Ch 4: Telecommunications and Networks ©© 2024 2022 Pavlovych Pavlovych ©© 2018 2018 CENGAGE, CENGAGE, ALL ALL RIGHTS RIGHTS RESERVED RESERVED Objectives Network topologies and network types Guided and wireless communications Network hardware devices and their functions Internet and Web; methods for connecting to the Internet Process and tools used in developing Web content and applications Internet and Web applications Intranets and Extranets Internet of Things (IoT); potential issues and barriers in expansion of the IoT Cloud computing. Challenges. Pros and cons of private and hybrid cloud computing compared to public cloud computing Network Fundamentals Computer network: the communications media, devices, and software needed to connect two or more computer systems or devices Network nodes: the computers and devices on the networks Organizations can use networks to share hardware, programs, and databases Network Topology (1 of 4) Network topology o The shape or structure of a network, including the arrangement of the communications links and hardware devices on the network Three most common network topologies o Star network o Bus network o Mesh network Network Topology (2 of 4) Star network In a star network, all network devices connect to one another through a single central hub node Network Topology (3 of 4) Bus network In a bus network, all network devices are connected to a common backbone that serves as a shared communications medium Network Topology (4 of 4) Mesh network Mesh networks use multiple access points to link a series of devices that speak to each other to form a network connection across a large area Network Types A personal area network (PAN) supports the interconnection of information technology close to one person A local area network (LAN) connects computer systems and devices within a small area (e.g., an office or a home) A metropolitan area network (MAN) connects users and their devices in an area that spans a campus or city A wide area network (WAN) connects large geographic regions o may involve transborder data flow WANs consist of: o Computer equipment owned by the user o Data communications equipment and telecommunications links provided by various carriers and service providers LAN Typical LAN All network users within an office building can connect to each other’s devices for rapid communication For instance, a user in research and development could send a document from her computer to be printed at a printer located in the desktop publishing centre Most computer labs employ a LAN to enable the users to share the use of high-speed and/or color printers and plotters as well as to download software applications and save files Client/Server Systems Client/server architecture features multiple computer platforms dedicated to special functions, e.g., database management, printing, or communications A client is any computer that sends messages requesting services from the servers on the network A database server sends only the data that meets a specific query—not the entire file or database Channel Bandwidth Channel bandwidth: the rate at which data is exchanged o Usually measured in bits/s Broadband communications: a relative term; a telecommunications system that can transmit data very quickly (usually, at a rate similar to that of a typical LAN) Communications Media (1 of 9) Two broad categories o Guided (wired) transmission media: signals are guided along a solid medium o Wireless: the signal is broadcast over airwaves as a form of electromagnetic radiation [typically well below optical frequencies] TABLE 4.1 Guided transmission media types Media Form Description Advantages Disadvantages Twisted-pair Twisted pairs of copper wire, Widely available Limitations on wire shielded or unshielded; used for transmission speed and telephone service distance Coaxial cable Inner conductor wire surrounded Cleaner and faster data More expensive than by insulation transmission than twisted-pair wire twisted-pair wire Fiber-optic Many extremely thin strands of Diameter of cable is much smaller Expensive to purchase cable glass bound together in a than coaxial cable; less distortion and install sheathing; uses light beams to of signal; capable of high transmit signals transmission rates Communications Media (2 of 9) Wireless Technologies o Wireless transmission involves the broadcast of communications in one of three frequency ranges Radio, microwave, or infrared frequencies o In some cases, use of wireless communications is regulated The signal must be broadcast within a specific frequency range to avoid interference with other wireless transmissions TABLE 4.2 Frequency ranges used for wireless communications Technology Description Advantages Disadvantages “Radio” frequency Operates in the 3 KHz – 300 MHz Almost none Signal is highly susceptible to interception range range Microwave— High-frequency radio signal (300 Avoids cost and effort to lay Must have unobstructed line of sight terrestrial and MHz – 300 GHz) sent through the cable or wires; capable of between sender and receiver (at higher satellite frequency atmosphere and space (often high-speed transmission frequencies); signal is susceptible to range involves communications satellites) interception Infrared frequency Signals in the 300 GHz – 400 THz Lets you move, remove, and Must have unobstructed line of sight range frequency range install devices without between sender and receiver; transmission (Starlink laser backbone in space: expensive wiring is effective only for short distances (unless 200–300 THz (1000–1550 nm) Extremely high speeds are in vacuum) possible (in theory) Communications Media (3 of 9) Near field communication (NFC): a very short-range wireless connectivity technology o Designed for consumer electronics, cell phones, and credit cards o When powered: highway transponders (tens of meters range) Bluetooth: a wireless communications specification that describes how cell phones, computers, personal digital assistants, etc., can be interconnected Wi-Fi o A wireless technology trademark owned by the Wi-Fi Alliance o Employs a wireless access point (a transmitter with an antenna) that receives the signal and decodes it Translates signals into a radio signal and sends it to device’s wireless adapter o The area covered by a wireless access point is called a “hot spot” (more are needed for a wider area) Communications Media (4 of 9) TABLE 4.3 IEEE 802.11 wireless local area networking standards Wireless Maximum Data Rate Networking per Data Stream Protocol Comments IEEE 802.11a 54 Mbps Transmits at 5 GHz, incompatible with 802.11b and 802.11g IEEE 802.11b 11 Mbps First widely accepted wireless network standard and transmits at 2.4 GHz; equipment using this protocol may occasionally suffer from interference from microwave ovens, cordless telephones, and Bluetooth devices IEEE 802.11g 54 Mbps Equipment using this protocol transmits at 2.4 GHz and may occasionally suffer from interference from microwave ovens, cordless telephones, and Bluetooth devices IEEE 802.11n 65–300 Mbps Employs multiple input, multiple output (MIMO) technology, which allows multiple data streams to be transmitted over the same channel using the same bandwidth that is used for only a single data stream in 802.11a/b/g; can transmit at either 2.4 GHz or 5 GHz IEEE 802.11ac 433 Mbps–1.3+ Gbps An 802.11 standard that provides higher data transmission speeds and more and later.11ax stable connections  Communications Media (5 of 9) Wi-Fi network In a Wi-Fi network, the user’s computer, smartphone, or cell phone all have wireless adapters that translate data into a radio signal and transmit it using an antenna Communications Media (6 of 9) Microwave Transmission o Microwave is a high-frequency (300 MHz–300 GHz) signal sent through the air o WiFi o Cellular communication o Common forms of satellite communications: Geostationary satellites Low earth orbit (LEO) and mid- (MEO) satellites Communications Media (7 of 9) Satellite transmission Communications satellites are relay stations that receive signals from one Earth station and rebroadcast them to another. Communications Media (8 of 9) Historical perspective o 1G (first generation) of wireless communications standards: originated in the 1980s; based on analog communications o 2G (second generation) employed fully digital networks; superseded 1G networks in the early1990s. GSM is the best-known standard o 3G supports wireless voice and broadband speed data communications in a mobile environment at speeds of 2 to 5+ Mbps (definitions of 3G vary) o 4G wireless provides increased data transmission rates 3 to 20 times the speed of 3G networks for mobile devices (up to 100 Mbps) o 4G networks are based on Long Term Evolution (LTE) LTE is a standard for wireless communications for mobile phones based on packet switching o 5G: incremental improvements, allow very high speed on higher freqs (24+ GHz) Communications Media (9 of 9) 5G Wireless Communications o Expected characteristics Higher data transmission rates Lower power consumption Higher connect reliability and more coverage Lower infrastructure costs o Deployment started around 2017 Communications Hardware TABLE 4.4 Common communications devices (and less-common too) Device Function Modem Translates data from a digital form (as it is stored in the computer) into an analog signal that can be transmitted over ordinary analog telephone, cable TV, etc. lines Fax modem Combines a fax with a modem; facsimile devices, commonly called fax devices, allow businesses to transmit text, graphs, photographs, and other digital files via networks Multiplexer Allows several communications signals to be transmitted over a single communications medium at the same time, thus saving expensive long-distance communications costs PBX (private branch exchange) Manages both voice and data transfer within a building and to outside lines; PBXs can be used to connect hundreds of internal phone lines to a few outside phone company lines Front-end processor Manages communications to and from a computer system serving many people Switch Uses the physical device address in each incoming message on the network to determine which output port it should forward the message to reach another device on the same network Bridge Connects one LAN to another LAN where both LANs use the same communications protocol Router Forwards data packets across two or more distinct networks toward their destinations through a process known as routing; often, an Internet service provider (ISP) installs a router in a subscriber’s home that connects the ISP’s network to the network within the home Gateway Serves as an entrance to another network, such as the Internet Part 2: Communications Software (1 of 2) Network operating system (NOS) o Systems software that controls the computer systems and devices on a network o Linux, UNIX, Windows Server, and macOS are common NOSs Network-management software o Collects data to guide decisions regarding upgrades or other changes o Locates telecommunications errors and potential network problems Communications Software (2 of 2) Mobile device management (MDM) software o Manages and troubleshoots mobile devices remotely, pushing out applications, data, patches and settings o A central control group can maintain group policies for security, control system settings, ensure malware protection is in place for mobile devices used across the network, and make it mandatory to use passwords to access the network Software-Defined Networking (SDN) o An emerging approach to networking o Allows network administrators to have programmable central control of the network via a controller without requiring physical access to all the network devices The Internet and World Wide Web The Internet is international in scope with users on every continent Impact on world politics Internet censorship o Some countries try to control Internet content and services ARPANET o Ancestor of the Internet o Project started by the U.S. Department of Defense (DoD) in 1969 Internet Protocol (IP) enables computers to route communications traffic from one network to another How the Internet Works (1 of 4) Internet backbone: one of the Internet’s high-speed, long-distance communications links IP protocol o The set of rules used to pass packets from one host to another Transmission Control Protocol (TCP): the widely used transport layer protocol that most Internet applications use with IP IP address: a 32-bit (in IPv4, or 128-bit in IPv6) number that identifies a computer on the Internet o max ∼232, or ∼264 addresses (not 2128!) How the Internet Works (2 of 4) Routing messages over the Internet Data is transmitted from one host computer to another on the Internet. How the Internet Works (3 of 4) Uniform Resource Locator (URL): a Web address that specifies the exact location of a Web page using letters and words that can later map to an IP address and a host location Internet Corporation for Assigned Names and Numbers (ICANN) is responsible for managing IP addresses and Internet domain names o Domain names must adhere to strict rules How the Internet Works (4 of 4) TABLE 4.5 Number of domains in U.S. top-level domain affiliations as of 2015 Affiliation ID Affiliation Number of Hosts biz Business sites 2,428,269 com All types of entities including nonprofits, 123,743,892 schools, and private individuals edu Post-secondary educational sites 7,446 gov [USA] government sites 5,503 net Networking sites 15,805,152 org Nonprofit organization sites 10,984,293 Source: Domain Count Statistics for TLDs, http//research.domaintools.com/statistics/tld-counts/. Accessing the Internet (1 of 3) Connecting via LAN server o Connection method of businesses and organizations that manage a local area network (LAN) Connecting via Internet service providers o Internet service provider (ISP) is any organization that provides Internet access to people o You must have an account with the service provider along with software and devices that support a connection via TCP/IP Accessing the Internet (2 of 3) Several ways to access the Internet Users can access the Internet in several ways, including using a LAN server, telephone lines, a highspeed service, or a wireless network. Accessing the Internet (3 of 3) Dial-up Internet connection uses modem and a standard phone line o obsolete Other options include: o Cable modem connections o DSL (ADSL, VDSL) connections o Fiberoptic connections (FTTx) o Satellite connections Wireless Connection o Internet service over cellular and Wi-Fi networks has become common o WiMAX: hybrid of cellular and wireless LAN technologies. Common in rural and other sparsely-populated areas How the Web Works (1 of 2) The Internet o The infrastructure on which the Web and other services exist o Made up of computers, network hardware such as routers and fiber-optic cables, software, and the TCP/IP protocols The World Wide Web (web) o Just one of many possible services on the network o Consists of server and client software, the hypertext transfer protocol (http), standards, and markup languages that combine to deliver information and services over the Internet How the Web Works (2 of 2) Web site: a collection of pages on one particular topic, accessed under one Web domain Web browser: Web client software used to view web pages o Examples: Chrome, Edge, Firefox, Safari, and others Hyperlink: highlighted text or graphics in a web document that, when clicked, opens a new Web page HTML: the standard page description language for web pages CSS: defines the visual appearance of content in a web page JavaScript: A popular programming language for client-side web applications o Used to create web pages that respond to user actions Other Web Programming Languages Java o An object-oriented programming language from Sun Microsystems (now Oracle) influenced by C and C++ o Allowed small programs (applets) to be embedded within an HTML document o Now, used mostly on server side Other client-side programming languages include: o ASP.NET o C o C++ o Perl o PHP o Python Web Services Standards and tools that streamline and simplify communication among web sites HTML5 and/or XML o The key to Web services o Used within a Web page to describe and transfer data between web service applications Amazon Web Services (AWS) o Basic infrastructure that Amazon employs to make the contents of its online catalog available to other web sites or software applications Developing Web Content and Applications Popular tools for creating web pages and managing web sites o Adobe Dreamweaver, RapidWeaver (for Mac developers), and SeaMonkey Composer o Many other commercial and free products Products to develop Web content and interconnect web services o Microsoft’s.NET platform: allows developers to use various programming languages to create and run programs Internet and web Applications (1 of 9) Web 2.0 and the Social Web o Web 2.0: web as a computing platform that supports software applications and the sharing of information among users o Social networking web sites enable users to share information abut themselves and to find, meet, and converse with others o Internet applications are available that run in a web browser and do not require local installation Internet and web Applications (2 of 9) News o The web is a powerful tool for keeping informed about local, state, national, and global news Education and Training o Web is ideally suited as a tool for sharing information and a primary repository of information on all subjects o Distance education offers classes via the web Job Information o Providing information about a businesses and its products via web site and social media increases the company’s exposure and reputation o The web is an excellent source of job-related information o Examples: www.linkedin.com, www.monster.com, and www.careerbuilder.com Internet and web Applications (3 of 9) Search Engines and Web Research o Search engine Information on the Web is found by specifying keywords The market is dominated by Google o Search engine optimization (SEO) is a process for driving traffic to a web site by using techniques that improve the site’s ranking in search results o Online research databases allow visitors to search for information in thousands of journal, magazine, and newspaper articles Internet and Web Applications (4 of 9) Instant messaging o Online, real-time communication between two or more people who are connected via the Internet Microblogging, Status Updates, and News Feeds o Twitter allows users to send short text updates from a smartphone or a web browser to their Twitter followers o Popularity of Twitter has caused social networks, such as Facebook, LinkedIn, and Tumbler, to include Twitter-like news or blog post feeds Internet and Web Applications (5 of 9) Conferencing o The Internet has made it possible for those involved in teleconferences to share computer desktops o GoToMeeting, Zoom, Google Meet enable employees to attend training without leaving their assigned stations o Telepresence systems use high-resolution video and audio with high-definition displays o Google Meet, Skype and many others allow video chats Internet and Web Applications (6 of 9) Blogging and Podcasting o Web log (blog): a Web site that people can create and use to write about their observations, experiences, and opinions on a wide range of topics o Video log (vlog): blogging with video content (TikTok) o Podcast: an audio broadcast over the Internet (name: iPod audio player) Online Media and Entertainment o Content streaming: a method of transferring large media files over the Internet The data stream of voice and pictures plays continuously as the file is being downloaded (e.g., YouTube, Netflix and others) o Music Internet radio is digitally delivered to your computer over the Internet Downloaded music may employ Digital Rights Management (DRM) technology to limit the user’s ability to make copies Internet and Web Applications (7 of 9) Online Media and Entertainment (continued) o Movies, Video, and Television Hulu Web site and Internet-based television platforms (e.g., Netflix and Joost) provide television programming YouTube supports the online sharing of user-created videos o Online Games and Entertainment The market for Internet gaming is very competitive and constantly changing Many video games are available or are distributed online Internet and Web Applications (8 of 9) Shopping Online o Shopping on the Web can be convenient, easy, and cost effective o Retail stores provide access to many products that may be unavailable in local stores o Online clearinghouses, Web auctions, and marketplaces provide a platform for businesses and individuals to sell their products and belongings o eBay is the most popular online auction/marketplace o Businesses benefit from shopping online o Shopify: allows businesses open and manage their own online stores Internet and Web Applications (9 of 9) Travel, Geolocation, and Navigation o The Web has had a profound effect on the travel industry and the way people plan and prepare for trips o Mapping and geolocation tools MapQuest (one of the first!), Google Maps, and Bing Maps o Geographic information systems (GIS) provide geographic information layered over a map o Geo-tagging is possible on Twitter and Facebook Intranets and Extranets Intranet: an internal corporate network built using Internet and World Wide Web standards and technologies Extranet: a network based on Web technologies that links resources of a company’s intranet with its customers, suppliers, or other business partners Virtual private network (VPN): A secure connection between two points on the Internet Tunneling: the process by which VPNs transfer information by encapsulating traffic in IP packets over the Internet The Internet of Things (IoT) (1 of 3) Internet of Things (IoT) o A network of physical objects (things) embedded with sensors, processors, software, and network connectivity capability to enable them to exchange data with the manufacturer of the device, device operators, and other connected devices Sensor: a device that is capable of sensing something about its surroundings such as o Pressure, temperature, humidity, pH level, motion, vibration, or level of light https://toronto.citynews.ca/2023/07/08/toronto- lake-ontario-temperatures-conditions/ The Internet of Things (IoT) (2 of 3) The Internet of Things The IoT is a network of physical objects or “things” embedded with sensors, processors, software, and network connectivity capability to enable them to exchange data with the manufacturer of the device, device operators, and other connected devices. The Internet of Things (IoT) (3 of 3) Examples of using sensors and the IoT to monitor and control key operational activities: o Asset monitoring o Construction o Agriculture o Manufacturing o Monitoring parking spaces o Predictive Maintenance o Retailing o Traffic monitoring Cloud Computing Cloud computing: a computing environment in which software and storage are provided as an Internet service and accessed with a Web browser Advantages to businesses: o Businesses can save on system design, installation, and maintenance o Increased efficiency and reduce the costs of new product and service launches o Employees can access corporate systems from any Internet-connected computer Public Cloud Computing A service provider owns and manages the infrastructure with cloud user organizations (tenants) accessing slices of shared hardware resource via the Internet Public cloud computing can be a faster, cheaper, and more agile approach to building and managing your own IT infrastructure However, data security is a key concern o Because when using a public cloud computing service, you are relying on someone else to safeguard your data Three main types of services: o Infrastructure as a service (IaaS) o Software as a service (SaaS) o Platform as a Service (PaaS) Private and Hybrid Cloud Computing Private cloud environment o A single tenant cloud o Organization often implement due to concerns that their data will not be secure in a public cloud o Can be divided into two types: On-premise private cloud Service provider-managed private cloud Hybrid cloud o Composed of both private and public clouds integrated through networking o Organizations typically use the public cloud to run applications with less sensitive security requirements o Runs more critical applications on the private portion of the hybrid cloud Summary A network has many fundamental components, which enable people to meet personal and organizational objectives Together, the Internet and the WWW provide a highly effective infrastructure for delivering and accessing information and services Organizations can use the Internet of Things (IoT) to capture and analyze streams of sensor data to detect patterns and anomalies in order to have a considerable impact on the event outcome Cloud computing provides access to state-of-the-art technology at a fraction of the cost of ownership and without the lengthy delays that can occur when an organization tries to acquire its own resources