ITM100 - Chapter 7; telecommunication, the internet, and wireless technology PDF

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Lecture 7 notes. 10 key concepts. diagrams, graphs and description...

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1 | CHAPTER 7: TELECOMMUNICATIONS, THE INTERNET, AND WIRELESS TECHNOLOGY  NETWORKING AND COMMUNICATIONS Convergence: Telephone networks and computer networks converging into single digital network using Internet standards Broadband: More than 76 percent U.S. Internet users have broadband access wide bandwidth data transmission which transports multiple signals at a wide range Higher number of users of IT = broader areas for health care and education (south korean, japan) Broadband wireless: Voice, data communication are increasingly taking place over broadband wireless platforms High volume of traffic What is a computer network? Page: 254-255 Two or more connected computers: (remember Metcalfe’s Law) More people use it theory Major components in simple network Client and server computers ■ Client is the laptop (device) asking for a service (database, software) Network interfaces (N I C s) ■ Hardware would be a card to communicate with operating system Connection medium ■ Physics of how communication is carried out ■ Copper ■ Coax cables ■ Satellite - short cable operating at each and every device ■ Radio communication - cellular connection and frequency ■ Long-haul waves - transmitting from towers ■ Fiber optics - save a lot of values - white wire Network operating system (N O S) ■ Network system within softwares like windows ■ Handles traffic Hubs, switches, routers ■ Provide initial connection to the hardware ■ Hub - connect network to all connected devices ■ Switch - more intelligent - send to a specific destination ■ Router - most intelligent - different network to the specific and right destination Software-defined networking (S D N) Functions of switches and routers managed by central program

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Pcl - happening all over the world, they have to find network and where to store data Powerful

   Components of a simple computer server

 NETWORKS IN LARGE COMPANIES ● Hundreds of local area networks (L A N s) linked to firm-wide corporate network ○ hundreds of PC ● Various powerful servers ○ Website, corporate intranet (interior of the organization and filters the data), extranet (exterior of the organization) ○ Backend systems (finance, student hub, RAAMS) - handling millions of transaction ● Mobile wireless L A N s (Wi-Fi networks) ● Videoconferencing system – e.g. Zoom - better wifi then telecommunication network ●

Telephone network, wireless cell phones

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  KEY DIGITAL NETWORKING TECHNOLOGIES Client/server computing Distributed computing model Clients linked through network controlled by network server computer Server sets rules of communication for network and provides every client with an address so others can find it on the network Has largely replaced centralized mainframe computing The Internet: largest implementation of client/server computing open ● Protocol of asking (handshake) done throw a server Packet switching Method of slicing digital messages into parcels (packets), sending packets along different communication paths as they become available, and then reassembling packets at destination Previous circuit-switched networks required assembly of complete point-to-point circuit (very expensive) Packet switching more efficient use of network’s communications capacity

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When you hit enter or submit - the operating system takes the string of digital packets Packets are sent to different paths Going to different paths and they will guarantees that they will be

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reassembles once they arrive at the destination There are millions of alternate routes even if theres an issue at any routes

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 T C P /I P and connectivity Basically grabbing the information and transferring it different routes and reconstructing them when they arrive at the destination Protocols: rules that govern transmission of information between two points Transmission Control Protocol/Internet Protocol (T C P / I P) ● Common worldwide standard that is basis for the Internet Department of Defense reference model for T C P / I P ● Send without fear they will shut down ● They open to more than just military use ●

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Four layers (text book) ○ Application layer Communates with the transport layers ○ Transport layer Push to packets and to the define routes ○ Internet layer Going to local to others TCP/IP - internet protocol ○ Network interface layer responsible for packets at any network Application layer - hdtp

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  TYPES OF NETWORKS Signals: Digital versus analog Modem: translates digital signals into analog form (and vice versa) Digital is 1 or 0 (presence or the absence) converted to a wave - translate digital to analog Types of networks Local area networks (L A N s) ● Ethernet - communication between computers in the same network, protocol to communicate through the ethernet ● Client/server vs. peer-to-peer Wide area networks (W A N s) - far network connection Metropolitan area networks (M A N s) - bigger platforms Campus area networks (C A N s) - bigger platforms

  TRANSMISSION MEDIA AND TRANSMISSION SPEED Physical transmission media - determines the speed and volume Twisted pair wire (C A T5) - lowest speed Coaxial cable - covered in fibric wire

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Fiber optics cable - long distance communication ● Bounces of a plastc cable Wireless transmission media and devices ● Satellites ● Cellular systems Transmission speed ● Speed determined by a clock Bits per second (bps) - measure speed Hertz - one cycle of the median, speed of a clock Bandwidth - how wide of the spectrum can handle the traffic, volumes through the pipe how many mega bits are transmitted through the cable WHAT IS THE INTERNET The Internet World’s most extensive network Internet service providers (I S P s) - go between people who are buying and the overall global ISP ● Not set my government ■ Provide connections ■ Types of Internet connections ● Dial-up: 56.6 K bps - copper wire ● Digital subscriber line (D S L/F I O S): 385 K b p s –40 M b p s Cable Internet connections: 1–50 M b p s Satellite - highest speed T1/T3 lines: 1.54–45 M b p s - high bandwidth, high volume, reserve for manufacture INTERNET ADDRESSING AND ACHITECTURE ● Each device on Internet assigned Internet Protocol (IP) address ● 32-bit number, e.g. 207.46.250.119 ○ Moving to a new higher level once all the IP addresses are taken ● The Domain Name System (D N S) - easier to remember ● DNS and IP - Used to get your packets ○ Converts IP addresses to domain names ○ Hierarchical structure ○ Top-level domains ● ● ●

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 Top level domain - country of origin INTERNET ARCHITECTURE AND GOVERANCE Physical bankboard networks Network service providers Own trunk lines (high-speed backbone networks) Regional telephone and cable TV companies Provide regional and local access Professional organizations and government bodies establish Internet standards IAB - Internet Architecture Board - define the overall structure of the internet ICANN - Internet Corporation for Assigned Names and Numbers - manages the domain name syste W3C - World Wide Web Consortium - sets hypertext Markup Language and other programming standards for the web

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 Work under a domain name - > connected by campus network MAE - can be toronto to GTA Regional host - bell, roger - provide connection to the internet Telecommunications, internet - govern by the government  THE FUTURE INTERNET: IPv6 AND INTERNET 2 Internet and Ip are running out of domains and names ● IPv6 ○ New addressing scheme for I P numbers ○ Will provide more than a quadrillion new addresses ○ Not compatible with current I P v 5 addressing ● Internet2 ○ Advanced networking consortium ○ Universities, businesses, government agencies, other institutions ○ Developed high-capacity 100 G b p s testing network ○ Testing leading-edge new technologies for Internet INTERNET SERVICES AND COMMUNICATION TOOLS Internet services E-mail Chat and instant messaging - private and public Newsgroups - groups and bullet board Telnet - ability to work on another computer

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File Transfer Protocol (F T P) - rapidly receive files World Wide Web - jump from places on the internet Voice over I P (V o I P) Digital voice communication using I P, packet switching Using internet packet switching and digitize them and then analog back when it reaches destination Very low cost because you are using public network Concerns about security and safety

 Unified communications Communications systems that integrate voice, data, e-mail, conferencing Virtual private network (VPN) Secure, encrypted, private network run over Internet Lower cost than dedicated private network P P T P – Point to Point Tunnelling Protocol

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● Packets of data are encrypted (adds a level of security) Tunnelling – packets of data encrypted and wrapped inside IP packets Private server - they own all the data and network Uses public internet but the packets are encrypted and private, end to end Lower cost than other private network Common in financial transactions THE WEB ● The most popular Internet service, with universally accepted standards for storing, retrieving, formatting and displaying information by using a client/server architecture ●

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Hypertext: ○ Hypertext Markup Language (H T M L): transfer pages ○ Hypertext Transfer Protocol (H T T P): ○ Uniform resource locator (U R L): domain name/directory path/ webpage name Web servers ○ Software for locating and managing web pages

 SEARCHING FOR INFORMATION ON THE WEB Mobile search - using mobile device you are able to search, location sensing and GPS, most relevant for where you are located Semantic search - interpreting a sentence that predict what you are looking for, humming bird Social search - using social network, seeing your connection and find other common and relevant data Visual search - looking for picture, face, visual data is what is responded back Intelligent agent shopping bots - trivago, the best deal, you provide priameter Search engine marketing - using algorithm, making sure their business is top on the list, identifying as an ad on the first search Search engine optimization (S E O) - tricking the search engine with keywork repetition

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 THE FUTURE WEB (page 278) ● More tools to make sense of trillions of pages on the Internet ● Pervasive web - continue to expand, maybe in a visual, voice attactivate system, created different mediums (ie: cars) ● Internet of Things (I o T) - ● App Internet - more mobile traffic between apps, increase in cloud computing ● Increased cloud computing and S a a S ● Ubiquitous mobile connectivity ● Greater seamlessness of web as a whole  CELLULAR SYSTEMS Competing standards: Canada has both C D M A : United States only G S M : Rest of world, A T&T, T-Mobile Third-generation (3G) networks: 144 K bps Suitable for e-mail access, web browsing Slow, reliable, slowly removing Fourth-generation (4G) networks Up to 100 Mbps Suitable for Internet video

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LTE and Wi Max 5G Networks: Gigabit capacity Currently under development and early test deployments iPhone 12 is 5G capable, Bell, Telus, Rogers offer 5G connectivity in some cities Expensive upgrade, only in selective cities  WIRELESS COMPUTER NETWORKS AND INTERNET ACCESS ● Bluetooth (802.15) Links up to 8 devices in 10-meter area using low-power, radio-based communication ○ Useful for personal networking (PAN s) Wi-Fi (802.11) ○ Set of standards: 802.11 ○ Used for wireless LAN and wireless Internet access ○ Use access points: device with radio receiver/transmitter for connecting wireless devices to a wired LAN ○ Hotspots: one or more access points in public place to provide maximum wireless coverage for a specific area ○ Weak security features ■ People can access the packets ○

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W i Max (802.16) - not popular ○ Wireless access range of 31 miles ○ Require WiMax antennas

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 RADIO FREQUENCY IDENTIFICATION (RFID) ● Use tiny tags with microchips containing data about an item and location

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○ Typically attached to a device, it identifies itself ○ Incredibly used in inventory to see what is being sold ○ Automated toll system (hwy 407) - identifying the car Tag antennas to transmit radio signals over short distances to special RFID readers Common uses: ○ Automated toll-collection ○ Tracking goods in a supply chain Reduction in cost of tags making R F I D viable for many firms

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 WIRELESS SENSOR NETWORKS (WSN) Networks of hundreds or thousands of interconnected wireless devices Used to monitor building security, detect hazardous substances in air, monitor environmental changes, traffic, or military activity Devices have built-in processing, storage, and radio frequency sensors and antennas Require low-power, long-lasting batteries and ability to endure in the field without maintenance Major sources of “Big Data” and fueling “Internet of Things”

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15 TEN KEY CONCEPTS 1. 3G, 4G, 5G NETWORKS All generation of cellular system 3G - with transmission speeds 144 Kbps for mobile users to more than 2 Mbps for stationary users - Offer transmission speed appropriate for email and web browsing - Very old and very slow thus not making any more of them 4G - has a much higher speed up to 100 Mbps download speed and 50 Mbps upload speed - More than enough capacity for watching high-definition video on a device -

Long-term Evolution (LTE) and mobile worldwide interoperability for microwave access (WiMax) are the current 4G standards 5G - designed to support transmission of very large amounts of data in the gigabyte range - Fewer transmission delays and ability to connect more devices at once - 5G is used for smart cities - ie cars - and extensive use of Internet of Things (IoT) - Very expensive, thus making it available to selected countries  2. HYPERTEXT TRANSFER PROTOCOL (HTTP) Hypertext Markup Language (HTML) - page description language for specifying how text, graphics, video, and sound are placed on a web page - Creating dynamic links to other web pages - Originally designed to crease link static documents composed largely text - It is now being used for more social and interactive web applications Hypertext transfer protocol (HTTP) - transfer web pages files - Appart of the application layer in the transmission control protocol - Application use to exchange data -

The directory path and web page name are two piee of information within web address that help browser track down request page Uniform resource locator (URL) - URL tells the browser software exactly where to look for the information  3. INTERNET OF THINGS (IoT) - Based on billions of Internet-connected sensors throughout our physical world - The ability to transfer data over a network without requiring human-to-human or human-to-computer interaction  4. INTERNET PROTOCOL (IP) ADDRESS - A common addressing scheme that enables millions of computers to connect otherther -

in on giant global networks (internet) Found in the internet layer of the four layer department of defense reference Consist of a string of number

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When a user sends a message to another user on the internet - Message is first decomposed into packets - Each packet contains its destination address - [aclets are then sent from the client to arrive at a specific destination with a known address -

At the address the packet is reassembled into original message

 5. INTERNET SERVICE PROVIDER (ISP) - Are required to take down sites of copyright infringers they are hosting when the ISP are -

notified of the problem It is a commercial organization with a permanent connection to the internet that sells temporary connections to retail subscribers

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LOCAL AREA NETWORK (LAN) - Metcalfe’s law Helps us understand why computing resources are now so readily available Robert Metcalfe - inventor of Ethernet Increasing returns to scale that network member receive as more and more people join the network As numbers increase, the value of the entire system increases exponentially and continues to grow as members increase Social business value of digital networks - rapidly multiply the number of potential links

among network members - Operating system like Linus and Unix - They use TCP/IP protocol Definition: A telecommunications network that requires its own dedicated channels and that encompasses a lim- ited distance, usually one building or several buildings in close proximity.  7. RADIO FREQUENCY IDENTIFICAION (RFID) - System that provides a powerful technology for tracking the movement of goods throughout the supply chain - They use tiny tags (microchips) containing data about the item and its location will sinal over a short distance to RFID readers - These tags do not need line-of-sight, they are uniquely identified - It will emit radio waves in randes from 1 inch to 100 feet Definition: Technology using tiny tags with embedded microchips containing data about an item and its location to transmit short-distance radio signals to special RFID readers that then pass the data on to a computer for processing.  8. TRANSMISSION CONTROL PROTOCOL/INTERNET PROTOCOL (TCP/IP) - Uses a suite of protocols

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They establish a connection between the computer, sequences the transfer of packets and acknowledges the packets sent - IP is responsible for the delivery of packets and includes the disassembling and reassembling of packets during transmission Definition: Dominant model for achieving connectivity among different networks. Provides a universally agreed-on method for breaking up digital messages into packets, routing them to the proper ad- dresses, and then reassembling them into coherent messages.  9. VOICE OVER IP (VOIP) -

Delivers voice information in digital from using packets switching, avoiding the tolls charged by local and long-distance telephone network - VOIP can reduce communication and network management cost by 20-30% Definition: Facilities for managing the delivery of voice information using the Internet Protocol (IP).  10. WI-FI - 802.11 Wireless Internet access - Can transmit up to 54 Mbps in the 2.4-GHz range - Transmit up to 100 Mbps - Wireless device communication with a wired LAN using access points - Most popular use = for its high-speed wireless internet service -

Low-cost wireless LAM Disadvantage = susceptibility to interference from nearby system

 11. PACKET SWITCHING 

A method of slicing digital messages into parcels called packets Sending packets along different routes then reassembling them once they arrive at their destination It is more effective - the message is first broken down into smaller packets - send packet to the right address and checking for transmission errors ...