Information Technology Essentials Lecture 10 PDF

Information Technology Essentials — Lecture 10 Dr. Karim Lounis Fall 2024 Dr. Karim Lounis Information Technology Essentials Fall 2024 1 / 38  Computer Networks Computer Networks Networks Co...

Information Technology Essentials — Lecture 10 Dr. Karim Lounis Fall 2024 Dr. Karim Lounis Information Technology Essentials Fall 2024 1 / 38  Computer Networks Computer Networks Networks Computer Networks (Part 2) Dr. Karim Lounis Information Technology Essentials Fall 2024 2 / 38  Computer Networks Computer Networks Computer Networks Definition Computer Network. It is a set of computers and networking devices that are Communication connected together Protocol. Is a set of standard using communication means, rules, regulations, e.g., cables and and radio, procedures that define how the communication between enabeling resource sharing, data exchange, and collaboration. two devices will reliably take place (initialization, communication, and termination): In a computer network: There’re various communication protocols out there. Each protocol pro- We exchange packets (∼ network traffic). vides some services to the connected computer. E.g.,: Applications generate messages. HTTP. HyperText Transfer Protocol, is used by a computer to Thetransfer messages contain web pages textbrowser (your (e.g., will htmlgenerate HTTP messages). code), data, voice, video, images, etc. HTTPS. HyperText Transfer Protocol — Secure, is used by a com- The operating system takes messages from puter to transfer web pages securely. various applications to creates packets. FTP. the Through Filecomputer’s Transfer Protocol, is used network card, by aarecomputer packets transmited to transfer into the communicaiton medium (i.e., wired or a wireless medium). use other (download and upload) files over a network. You can still protocols to download files (e.g., HTTP, HTTPS, SFTP, etc). Dr. Karim Lounis Information Technology Essentials Fall 2024 3 / 38  Computer Networks Computer Networks Computer Networks Definition Computer Network. It is a set of computers and networking devices that are Communication connected together Protocol Is a set of standard using communication means, rules, regulations, e.g., cables and and radio, procedures that define how the communication between enabeling resource sharing, data exchange, and collaboration. two devices will reliably take place (initialization, communication, and termination): In a computer network: WeDHCP. exchangeDynamic packetsHost Configuration (∼ network Protocol, is used by a com- traffic). puter to obtain an IPv4 address so that it can communicate. Applications generate messages. TheSMTP. Simple messages Mail Protocol, contain is used text (e.g., by a computer to send emails. html code), data, voice, video, images, etc. POP3. Post Office Protocol v3, is used by a computer to retrieves Theemails operating (yoursystem takesapplication mail client messages from will retrieve the emails for you). various applications to creates packets. IMAP. Internet Message Access Protocol, is used by a computer to Through theemails retrieves computer’s while network keeping card, packets are transmited into the copies. communicaiton medium (i.e., wired or a wireless medium). Dr. Karim Lounis Information Technology Essentials Fall 2024 4 / 38  Computer Networks Computer Networks Computer Networks Definition Computer Network. It is a set of computers and networking devices that are Communication connected together Protocol Is a set of standard using communication means, rules, regulations, e.g., cables and and radio, procedures that define how the communication between enabeling resource sharing, data exchange, and collaboration. two devices will reliably take place (initialization, communication, and termination): In a computer network: WeDNS. Domain exchange Name packets (∼ System, networkistraffic). used by your computer to resolve domaine names into IPV4 address. Certain connected computer are Applications generate messages. identified by a human-readable name, called domaine name (e.g., Thewww.ensia.edu.dz). messages contain text (e.g., html Your computer needs to know the IPv4 ad- code), data, voice, video, images, etc. dress of that computer given its domain name — it uses DNS. The operating system takes messages from Telnet. Is used by a computer to connect to a remote computer and various applications to creates packets. execute commands. It uses username and password in plaintext. Through the computer’s network card, packets are transmited into the SSH. Securemedium communicaiton Shell, is(i.e., used wired by a computer to securely or a wireless medium). connect to a remote computer and execute commands. Dr. Karim Lounis Information Technology Essentials Fall 2024 5 / 38  Computer Networks Computer Networks Computer Networks Definition Computer Network. It is a set of computers and networking devices that are ☞ Communication DNS is together connected used byProtocol your usingcomputer Is a settoofresolve communication standarddomaine means, rules, e.g., names regulations, cables into radio, and IPV4 and address. proceduresThethat string definewww.cnn.com how the communication is composed enabeling resource sharing, data exchange, and collaboration.between of a subdomain two devices wwwwill reliably of the domain take place cnn.com, (initialization, of the top-domain communication,.com.and termination): In a computer network: WeDHCP. exchangeDynamic packetsHost Configuration (∼ network Protocol, is used by a com- traffic). puter to obtain an IPv4 address so that it can communicate. Applications generate messages. TheSMTP. Simple messages Mail Protocol, contain is used text (e.g., by a computer to send emails. html code), data, voice, video, images, etc. POP3. Post Office Protocol v3, is used by a computer to retrieves Theemails operating (yoursystem takesapplication mail client messages fromwill retrieve the emails for you). various applications to creates packets. IMAP. Internet Message Access Protocol, is used by a computer to Through theemails retrieves computer’s while network keeping card, copies.packets are transmited into the communicaiton medium (i.e., wired or a wireless medium). Dr. Karim Lounis Information Technology Essentials Fall 2024 6 / 38  Computer Networks Computer Networks Computer Networks Definition Computer Network. It is a set of computers and networking devices that are Communication connected together Protocol Is a set of standard using communication means, rules, regulations, e.g., cables and and radio, procedures that define how the communication between enabeling resource sharing, data exchange, and collaboration. two devices will reliably take place (initialization, communication, and termination): In a computer network: WeIP. Internetpackets exchange Protocol, (∼ isnetwork used by traffic). your computer as a carrying proto- col for HTTP, HTTPS, DNS, Telnet, SSH, FTP, POP3, etc, so that Applications generate messages. the packets reliably arrive to destination (it adds IPv4 addresses). The messages contain text (e.g., html TCP. code), Transmission data, Control voice, video, images,Protocol, etc. is used by a computer reliably establish end-to-end connection. Allows a local application to talk The operating system takes messages from to another application on a remote computer. Runs on top of IP. various applications to creates packets. Ethernet. Through Is a protocol the computer’s that card, network allows two network packets devices to are transmited com- into the municate using a direct link (It adds the physical communicaiton medium (i.e., wired or a wireless medium). MAC addresses). Dr. Karim Lounis Information Technology Essentials Fall 2024 7 / 38  Computer Networks Computer Networks Networking (Exercise) Answer the following questions: How do we call the information that is added by each protocol to the packet we want to send over the network? Which protocol allows a computer to be assigned an IPv4 address? How do we call the process that allows the use of multiple protocols? Which protocol allows secure access to website? Which protocol allows a computer to securely establish a connection with a remote computer and run commands? Which protocol allows packets to be carried out to destination? Which communication protocol allows a computer to retrieve the IPv4 address of a webserver? Dr. Karim Lounis Information Technology Essentials Fall 2024 8 / 38  Computer Networks Computer Networks Networking Devices Dr. Karim Lounis Information Technology Essentials Fall 2024 9 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼ road network: shops, gas station, parking lots, and offices in a city 2 Routers. These are devices responsible for directing packets. ∼ road network: road directional signs (to citites) 3 Switches. These are devices responsible for directing packets. ∼ road network: facilities directional signs (e.g., restaurant, shops, police office, parking lot, bus station, school, etc) Dr. Karim Lounis Information Technology Essentials Fall 2024 10 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼1 road network: Servers. shops, that Computers gas station, provide parking lots,services, users with and offices suchinas:a city 2 Routers. These File are Manages Server. devices responsible and providesfor directing access packets. to files. ∼ road Web network: Server. road Hostssigns and directional and serves webpages. signs outside citites 3 Switches. These are devices responsible for directing packets. Database Server. Manages and provides access to databases. ∼ road network: directional signs inside the citites Application Server. Manages and provides access to applications. Mail Server. Manages and transfers emails. Print Server. Manages a set of printers. DNS Server. Resolves domaine names to IP addresses. DHCP Server. Assigns and manages IP addresses in a network. DB Server. Provides access to a database through a DBMS. And more... Dr. Karim Lounis Information Technology Essentials Fall 2024 11 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ☞∼ 1 Database road Server. network: Servers. shops,Isthat Computers a server gas that station, provide runwith parking users alots, database management and offices services, suchinas:a city system 2 Routers.(e.g., MySQL) These File to manage are Manages Server. and devices responsibleprovide and providesfor access directing access to a database. packets. to files. ∼ road Webnetwork: Server. road Hostssigns and directional and serves webpages. signs outside citites 3 Switches. These are devices responsible for directing packets. Database Server. Manages and provides access to databases. ∼ road network: directional signs inside the citites Application Server. Manages and provides access to applications. Mail Server. Manages and transfers emails. Print Server. Manages a set of printers. DNS Server. Resolves domaine names to IP addresses. DHCP Server. Assigns and manages IP addresses in a network. DB Server. Provides access to a database through a DBMS. And more... Dr. Karim Lounis Information Technology Essentials Fall 2024 12 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. Database. ∼1 road A Computers collection network: Servers. shops, of gaslogically-related that station, provide parkingfiles, containing lots,services, users with suchorganized and offices inas:a city information 2 Routers. about These File specific entities, are Manages Server. in devices responsibleparticular and providesfor field, directing access and is stored packets. to files. in a way that allows ∼ road easy retrieval, network: management, and updating of information. Web Server. road Hostssigns and directional and serves webpages. signs outside citites 3 Switches. These are devices responsible for directing packets. Database Server. Manages and provides access to databases. ∼ road network: directional signs inside the citites Application Server. Manages and provides access to applications. Mail Server. Manages and transfers emails. Print Server. Manages a set of printers. DNS Server. Resolves domaine names to IP addresses. DHCP Server. Assigns and manages IP addresses in a network. DB Server. Provides access to a database through a DBMS. And more... Dr. Karim Lounis Information Technology Essentials Fall 2024 13 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. Database. ∼1 road A Computers collection network: Servers. shops, of gaslogically-related that station, provide parkingfiles, containing lots,services, users with suchorganized and offices inas:a city information 2 Routers. about These File specific entities, are Manages Server. in devices responsibleparticular and providesfor field, directing access and is stored packets. to files. in a way that allows ∼ road easy retrieval, network: management, and updating of information. Web Server. road Hostssigns and directional and serves webpages. signs outside citites 3 Switches. These are devices responsible for directing packets. Database Server. Manages and provides access to databases. ∼ road network: directional signs inside the citites Application Server. Manages and provides access to applications. Mail Server. Manages and transfers emails. Print Server. Manages a set of printers. DNS Server. If the database Resolves is of type domaine relational (i.e.,names uses to IP addresses. tabular structure to store data), youDHCP can query Server. Assigns and manages IP addresses in aQuery a database using SQL (Structured Lan- network. guage) to retrieve information from the database. E.g., DB Server. Provides access to a database through a DBMS. Select * from And more... student where name=“Abdeallah” Dr. Karim Lounis Information Technology Essentials Fall 2024 14 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼2 road network: Routers. shops, gas Computers station, for responsible parking lots,packets directing and offices in a city (routing) to 2 Routers. These the right are devices direction so that responsible the packets for directing reache packets. the correct destination: ∼ road In this network: figure, road signs the devices and directional labeled by 2620XM signsrepresent outside citites routers. 3 Switches. These are devices responsible for directing packets. The router maintains a data structure, ∼ road called routing network: table, whichdirectional dictates tosigns inside the citites the router where to sent a packet (which router’s exit interface) so that the packet goes to the right direction. An entry in the routing table would typi- cally contain: the IPv4 address of a re- mote network and the router’s output interface toward that network. Dr. Karim Lounis Information Technology Essentials Fall 2024 15 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼2 road network: Routers. shops, gas Computers station, for responsible parking lots,packets directing and offices in a city (routing) to 2 Routers. These the right are devices direction so that responsible the packets for directing reache packets. the correct destination: The ∼figure road network: road signs and below illustrates the directional routing signs table outside citites 8: of Router 3 Switches. These are devices responsible for directing packets. The router constructs its ∼ road routing tables network: either, man- directional signs inside the citites ually by the network ad- ministrator (root in Unix- like OSs), or dynamically, using a routing protocol. There are various rout- ing protocols, e.g., RIP, OSPF, BGP, ISIS, etc. Dr. Karim Lounis Information Technology Essentials Fall 2024 16 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼ 3 road network: Switches. shops, responsible Devices gas station,forparking lots, packets directing and offices in aright to the city 2 Routers. Thesewithin destination are devices a local responsible network: for directing packets. ∼ road End-point network: devices, e.g.,road signs and computers, directional server, printer,signs outsideconnected are directly citites 3 toSwitches. a networkThese through areadevices switche, via the for directing packets. responsible switch’s RJ45 ports. ∼ road network: directional signs inside the citites When a switch receives a packet, it de- livers it to the right destination based on the destination MAC address. The switch maintains a data structure, known as the MAC table, that stores (MAC address, RJ45 port). Dr. Karim Lounis Information Technology Essentials Fall 2024 17 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 4 Hubs. Devices responsible of broadcasting packets to all ∼ road network: a town square where everyone gathers 5 Repeaters. Devices responsible for extending packets reachability. ∼ road network: thumb-lifting, taxi, bus,... 6 Gateways. These are devices responsible for connecting two networks of different types ∼ road network: country boarders and costumers Dr. Karim Lounis Information Technology Essentials Fall 2024 18 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼ 4 road Hub.network: shops, gas station, Devices responsible parking lots, for boradcasting and to a packet offices in a city all computers 2 Routers. These connected are devices responsible for directing packets. to it: ∼ road End-point network: devices, e.g.,road signs and...,directional computers, server, cansigns outside directly citites be connected 3 toSwitches. a network These through area devices hub (RJ45). responsible for directing packets. When a hub∼ receives road network: directional a packet, it borad-signs inside the citites casts it to all output port (except source). A hub does not have the capabilities to read MAC addresses as the switch does. The hub is an old device and has been replaced by swtiches. Dr. Karim Lounis Information Technology Essentials Fall 2024 19 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼ 5 road network: Repeater. shops,responsible Devices gas station, forparking lots, and amplifying offices a signal so in a city that the 2 Routers. These are latter reaches devices longer responsible for directing packets. distances: ∼ roadswitches, Routers, network: road signsand hubs, and directional computer signs can outside citites be connected 3 toSwitches. a repeater These to extend their reachability. are devices responsible for directing packets. ∼ road network: directional signs inside the citites When a repeater receives a signal (that represents a packet), it amplifies it so that the signal can travel a longer dis- tance than the default distance. There are wired and wireless repeaters. Dr. Karim Lounis Information Technology Essentials Fall 2024 20 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼6 road network: Gateway. shops, gasthat A computer station, parking connects twolots, and offices different in a type (or same) city 2 Routers. Thesee.g., of networks, are devices responsible an Internet networkfor directing with packets. a cellular network (4G): ∼ road network: road signs and directional signs outside citites 3 Switches. These are devices responsible for directing packets. ∼ road network: directional signs inside the citites Here, the gateway is used to connect an Ethernet network to a DSL network. Dr. Karim Lounis Information Technology Essentials Fall 2024 21 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 7 Wireless routers. Devices responsible for directing (routing) packets among multiple networks. ∼ road network: GPS application — Google Maps 8 Wireless access points. Used to allow wireless access to networks. ∼ road network: An access point is like a ticket booth at an event. It controls access to a specific area. 9 Bridges. Allow to extend a network beyond its covered area. ∼ road network: bridges linking two locations Dr. Karim Lounis Information Technology Essentials Fall 2024 22 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼7 road network: Wireless shops, router. Is agas station, normal parking router but lots, and offices has wireless in a city capabilities. 2 Routers. These I.e., it can are deviceswith communicate responsible for directing other devices packets. using the radio medium. It can also act as a wireless access point. ∼ road network: road signs and directional signs outside citites 8 Wireless 3 Switches. access These arepoint. devicesIsresponsible a device that for allows to create directing a wireless packets. network, e.g., Wi-Fi network (viz., next slide). ∼ road network: directional signs inside the citites 9 Bridge. It is a device to bridge two network of same type. It can be a wired bridge as well as a wireless bridge. A Wi-Fi network is characterized by a name, called SSID, a password- based security mechanism (e.g., WEP, WPA, WPA2, WPA3), a radio channel (e.g., 1, 2,..., 13), an operational mode (infrastructure or AdHoc), a range (e.g., 50m-radius sphere), and other. Dr. Karim Lounis Information Technology Essentials Fall 2024 23 / 38  Computer Networks Computer Networks Networking Devices There are various networking devices (here the symbol ∼ refer to analogy): 1 Servers. Computers that r configured 2 provide users with services. ∼ road network: shops, gas station, parking lots, and offices in a city 2 Routers. These are devices responsible for directing packets. ∼ road network: road signs and directional signs outside citites 3 Switches. These are devices responsible for directing packets. ∼ road network: directional signs inside the citites Dr. Karim Lounis Information Technology Essentials Fall 2024 24 / 38  Computer Networks Computer Networks Proxy Servers Proxy server. Is an intermediate server that acts as a gateway between a user’s computer and the Internet (i.e., web-sites or web-services). Instead of connecting directly to a website or other Internet resources, the user’s computer first connects to the proxy server, and then the proxy server connects to the destination (website or web-service) on behalf of the user. ☞ Note that there are forward proxies and reverse proxies. Dr. Karim Lounis Information Technology Essentials Fall 2024 25 / 38  Computer Networks Computer Networks Proxy Servers Proxy server. Is an intermediate server that acts as a gateway between a user’s computer and the internet (i.e., web-sites or web-services). Proxies can be used for various purposes: 1 Bypassing Geo-restrictions. If the user is blocked from directly ac- cessing a website, they can go through the proxy to access that website.. If the country hosting a website is blocking some source IPv4 addresses, but allowing some proxies (installed in their lands or allies lands). If a country is blocking access to some websites, but allowing proxy connections (Access to website will be established in a tunnel). 2 Proxy DNS. Instead of using the ISP’s servers, you could configure your own DNS server at home (e.g., using piHole and OpenDNS) to protect your families. This would allow you to perform: Content Filtering and Access Control. Caching proxy servers can store copies of frequently accessed resources locally, reducing the need to fetch them from the Internet each time. Dr. Karim Lounis Information Technology Essentials Fall 2024 26 / 38  Computer Networks Computer Networks Proxy Servers Proxy server. Is an intermediate server that acts as a gateway between a user’s computer and the internet (i.e., web-sites or web-services). Proxies can be used for various purposes: 3 Improving Security. Proxies can be used to implement VPNs (Virtual Private Networks), i.e., secure communication tunnels. Proxy servers can act as an additional layer of security, inspecting and filtering incoming and outgoing traffic for malicious content. They can be part of a defense-in-depth strategy to protect against various online threats. 4 Enhancing Privacy and Anonymity. Users can use proxy servers to hide their IP addresses and enhance their online privacy (where users don’t want their identity or location to be easily traced). Use VPN client software, e.g., HotSpot Shield, Tor Browser, etc. 5 Load-Balancing. Reverse proxy servers can distribute incoming net- work traffic across multiple servers to ensure that no single server is overwhelmed (e.g., try $ nslookup www.youtube.com). Dr. Karim Lounis Information Technology Essentials Fall 2024 27 / 38  Computer Networks Computer Networks Proxy Servers Proxy server. Is an intermediate server that acts as a gateway between a user’s computer and the Internet (i.e., web-sites or web-services). This is an example of using HostSport Shield VPN client software: We got them, ooops, we lost them You can try that yourelf at: https://whatismyipaddress.com/ Dr. Karim Lounis Information Technology Essentials Fall 2024 28 / 38  Computer Networks Computer Networks Network Topologies Dr. Karim Lounis Information Technology Essentials Fall 2024 29 / 38  Computer Networks Computer Networks Network Topologies Networks may take various geometric forms, such as point-to-point, bus (multi-point), star (ring), mesh and full mesh, tree (hiearchical), and hybrid. Dr. Karim Lounis Information Technology Essentials Fall 2024 30 / 38  Computer Networks Computer Networks Networking (Exercise) Answer the following questions: What is the difference between a switch and a hub? What is the main function of a router? Which device should be used to extend the range of a signal? Which device is used to link the CCP network to Internet? Which device can be used to create a Wi-Fi network? Which device does not understand IPv4 and MAC addresses? Which network topology is used by DNS? Which devices allows users to go anonymous over the Internet? Dr. Karim Lounis Information Technology Essentials Fall 2024 31 / 38  Computer Networks Computer Networks Network Coverage Dr. Karim Lounis Information Technology Essentials Fall 2024 32 / 38  Computer Networks Computer Networks Network Coverage The range of a network spreads out over a geographic area. Based on covered area, we distinguish (PAN, LAN, MAN, and WAN): Personal Area Network. This network spreads out to a radius of few meters, like in a office or room. When a wireless technology is used, we call it a WPAN: Bluetooth Local Area Network. This network spreads out to a radius of 300m, like in house, entreprise, university, establishment, factory, etc. When a wireless technology is used, we call it a WLAN: Wi-Fi network Metropolitain Area Network. This network spreads out over a city. When a wireless technology is used, we call it a WMAN: WiMax Wide Area Network. This network spreads out over a country’s land, continent, or wolrd. E.g., the Internet. When a wireless technology is used, we call it a WWAN: cellular network (GSM, 3G, 4G, etc), Starlink, ect Dr. Karim Lounis Information Technology Essentials Fall 2024 33 / 38  Computer Networks Computer Networks Network Communication Technologies Dr. Karim Lounis Information Technology Essentials Fall 2024 34 / 38  Computer Networks Computer Networks Network Communication Technology Network technology in the context of computer networks defines the mech- anisms, techniques, tools, and communication protocols to facilitate the communication between the nodes of the network (two categories): Wired Communication Technologies. Facilitate communication and data access using wires and cables: Ethernet: used to implement LANs. DSL and ADSL: uses PSTN (Telephone lines) to access Internet. Optical fiber: uses optical fiber cable to access Internet (higher rate). Token-Ring: was once used to implement LANs. ☞ These technologies aim to guanratee a certain level of reliable commu- nication, fast communication, secure communicaiton, and global communi- caiton (The Backbone of Internet). Dr. Karim Lounis Information Technology Essentials Fall 2024 35 / 38  Computer Networks Computer Networks Network Communication Technology Network technology in the context of computer networks defines the mech- anisms, techniques, tools, and communication protocols to facilitate the communication between the nodes of the network (two categories): Wireless Communication Technologies. Facilitate communication and data access using electrical and electromagnetique radio waves: Satellites: Use cooperative satellites to broadcast information. Cellular technologies: Includes, GSM (2G), GPRS (2.5G), EDGE (2.75G), UMTS (3G), and LTE (4G), used to implement wireless tele- phone networks (voice only, data only, and then voice + data). Wi-Fi: used to create wireless LANs. Bluetooth: used to create wireless PANs. RFID: used for wireless authentication purposes. ☞ These technologies aim to guanratee a certain level of fast communica- tion, secure communicaiton, flexible communicaiton, cheap communication, and mobile communicaiton. Dr. Karim Lounis Information Technology Essentials Fall 2024 36 / 38  Computer Networks Computer Networks The Internet Internet. Is the Interconnection of Networks. It is the network that connects all public and private networks (that are connected) together. The Internet (1989) originated from the ARPANET (1969). Internet uses protocols such as IP and TCP to enable communication. Internet consists of all types of network devices, topologies, and tech- nologies we’ve discussed so far, enabling global access to information. Dr. Karim Lounis Information Technology Essentials Fall 2024 37 / 38  End of Presentation End. Dr. Karim Lounis Information Technology Essentials Fall 2024 38 / 38