After studying this chapter you will be able to understand: What is the purpose of search engines? List few URLs of websites you know. Which Boolean operators are used in the web search? What is the purpose of NEAR operator? What is the purpose of advanced search? What are sponsored listings? | Networks & Security Issues ADE100- Computer Literacy Lecture 09 Knowledge test What is the purpose of search engines? List few URLs of websites you know. Which Boolean operators are used in the web search? What is the purpose of NEAR operator? What is the purpose of advanced search? What are sponsored listings? Topics covered Introduction to LAN, WAN and Wireless networks Sharing on networks and network-related security issues Firewalls Security Protection against virus and spam emails What is hacking and protecting against it Computer Network Computer Networks Set of technologies that connects computers to share information Allows communication and collaboration between users Network computers are also called clients, nodes, workstations or servers. Share files, resources (printers, disk, modems) and programs Example: Internet Local Area Network- LAN Local Area Network (LAN) Contains printers, servers and computers Systems are close to each other Contained in one office or building . | Networks & Security Issues ADE100- Computer Literacy Lecture 09 Knowledge test What is the purpose of search engines? List few URLs of websites you know. Which Boolean operators are used in the web search? What is the purpose of NEAR operator? What is the purpose of advanced search? What are sponsored listings? Topics covered Introduction to LAN, WAN and Wireless networks Sharing on networks and network-related security issues Firewalls Security Protection against virus and spam emails What is hacking and protecting against it Computer Network Computer Networks Set of technologies that connects computers to share information Allows communication and collaboration between users Network computers are also called clients, nodes, workstations or servers. Share files, resources (printers, disk, modems) and programs Example: Internet Local Area Network- LAN Local Area Network (LAN) Contains printers, servers and computers Systems are close to each other Contained in one office or building Organizations often have several LANS Examples A network inside home Computer Lab Sharing on a LAN File server contains documents used by other computers. Wide Area Networks- WAN Wide Area Networks (WAN) Two or more LANs connected Over a large geographic area Typically use public or leased lines Phone lines Satellite Examples PTCL Internet Wireless Networks Data transmitted through the air LANs use radio waves WANs use microwave signals Easy to setup Difficult to secure Sharing on Networks Using networks we can Share various software and hardware resources. Files and folders Disk drives CD/DVD drives Application programs Printers Fax machine, etc. Sharing a Folder Select and right click a Folder Make it available for sharing Give permission for the selected users or everyone to access the folder Sharing a folder Shared Folder Indication Popular network security issues Finding a way into the network Unauthorized access to a network server Implement firewalls to prevent it TCP attacks If
