Introduction to Introduction to Computer Networks Computer Networks Aram Mohammad Abdulqadir Aram Mohammad Abdulqadir M.C.A M.C.A Department of Computer Science Department of Computer Science 1 Aram Mostowfi
Introduction toIntroduction to Computer Networks Computer Networks
Aram Mohammad AbdulqadirAram Mohammad AbdulqadirM.C.AM.C.ADepartment of Computer ScienceDepartment of Computer Science
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What is a computer?
•Computer is a machine which consists of various hardware parts and different softwares to process the stored data in memory.
So..
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What is a Computer Network? A network consists of 2 or more computers connected together and they can communicatecommunicate and shareshare resources.
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Why Networking?
1- Sharing information => i.e. data communication
Which one you prefer?
1 OR 2
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2- Sharing hardware or software
3- Centralize administration and support
• E.g. print document
• E.g. Internet-based, so everyone can access the same administrative or support application from their PCs
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How many kinds of Networks?
• Depending on one’s perspective, we can classify networks in different ways:
1. Based on transmission media: • Wired (UTP, coaxial cables, fiber-optic cables) • Wireless
2. Based on network size: • LAN, MAN and WAN
3. Based on management method: • Peer-to-peer and Client/Server
4. Based on topology (connectivity): • Bus, Star, Ring …
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Based on the Transmission Media• Wired Media:
1- Coaxial Cables1- Coaxial Cables 2-UTP Cables 2-UTP Cables 3-Fiber 3-Fiber Optic CablesOptic Cables
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Based on the Transmission Media• Wireless Media:
1- Wi-Fi1- Wi-Fi 2-Bluetooth 2-Bluetooth
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3-Infrared 3-Infrared 4-Microwave4-Microwave
Based on the Transmission Media• Wireless Media: (cont..)
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• Small network, short distance (1m -1000m)• Limited by no. of computers and distance
covered• Examples:
• Network inside the Student Computer Room• Network inside CF502• Network inside your home
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Based on the Network Size• Local Area Network - LAN
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• Metropolitan Area Network-MAN
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Based on the Network Size
• Medium size networks. Distance (1KM - 10KM)
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• A network that uses long-range telecommunication links to connect 2 or more LANs/computers housed in different places far apart.
• Towns, states, countries• More than 10 Kilometers
• Examples:• Network of our Campus• Internet
WANStudent Computer Centre
Your home
USA
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Based on the Network Size• Wide Area Network - WAN
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• Peer-to-peer network is also called workgroup• No hierarchy among computers all are equal• No administrator responsible for the network
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Based on the Management Method• Peer-to-Peer (P2P) Networks
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Based on the Management Method• Client-Server Network
• Computers are not same.• A computer (Server) administrate the others and its
responsible for all tasks in the network.
Server
Clients
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• How computers are connected together?How computers are connected together?
Bus Topology Ring Topology
Star Topology
Hub
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Based on Topology• Three simple topologies
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Nowadays Computer Networks have spread all over the world not only among computer machines although through many electronically devices to make life easier and use the resources as much as possible.
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