Networking concepts

it contains computer network definition & it's examples,advantages of networking,types of network,network architecture,network topologies and network security.

1. BASIC NETWORKING CONCEPTS PRESENTED BY : MS. AKANKSHA NARKHEDE

2. WE WILL LEARN ABOUT Definition of C omputer N etwork & its examples Advantages of Networking Network ing Components Types of Networks Network Architecture Network Topologies Network Security

3. DEFINTION S & EXAMPLES OF COMPUTER NETWORK DEFINTION S : A computer network is defined as the interconnection of two or more computers. It is done to enable the computers to communicate and share available resources. A computer network enables two or more computers to share data and peripheral devices. They communicate with each other, as well as work independently.

4. EXAMPLES: Network of roads ,railway lines , canals,etc . Communication network of telephone system which enable us to talk to anyone , anywhere & anytime . Network of Banks/ATMs(Automated Teller Machines). Radio /Television network broadcasts programs live across the globe. A network of malls , schools & hospitals , etc all over the country .

5. ADVANTAGES OF NETWORK ING File Sharing : Networks offer a quick and easy way to share a file directly. Resource Sharing : All computers in the network can share resources such as printers, fax machines, modem and scanners. Communication : Those on the network can communicate with each other via e- mails,instant messages,etc . Flexible Access : Networks allows their users to access files from computers throughout the network.

6. ADVANTAGES OF NETWORKING Sharing of Information : Computer network s enables us to share data and information with the computers that are located geographically large distance apart.

7. NETWORKING COMPONENTS Network Card : A   Network interface card  (also known as a  NIC ,  network card , or  network interface controller ) is an  electronic  device that connects a computer to a  computer network. It is considered a piece of computer hardware. Nowadays, most computer motherboards come with an inbuilt Network Card.

8. NETWORKING COMPONENTS Networking Cable : Networking cables  are networking hardware used to connect one network device to other network devices or to connect two or more computers to share  printers,  scanners etc . Different types of network cables, such as coaxial cable, optical fiber cable, and twisted pair cables, are used depending on the network's  physical layer , topology, and size .

9. NETWORKING COMPONENTS Modem : A  modem   is a hardware device that converts data from a digital format, intended for communication directly between devices with specialized wiring, into one suitable for a transmission medium such as telephone lines or radio.It converts the digital signals of a computer into analog signals to enable their transmission via phone lines.  

10. NETWORKING COMPONENTS Hubs & Switches : A   network switch  (also called  switching hub and   bridging hub ) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device.

11. TYPES OF NETWORKS

12. LOCAL AREA NETWORK(LAN) LAN is a network which is designed to operate over a small physical area such as an office, factory or a group of buildings. LAN’s are easy to design and troubleshoot Exchange of information and sharing of resources becomes easy because of LAN. In LAN all machines are connected to a single cable. Different types of topologies such as star, tree, bus, ring, etc Can be used .

13. METROPOLITAN AREA NETWORK(MAN) It is in between LAN & WAN technology that covers the entire city. It uses similar technology as LAN. It can be a single network such as cable TV network, or a measure of connecting a number of LAN’s o a large network so that resources can be shared LAN to LAN as well as device to device.

14. WIDE AREA NETWORK(WAN) When network spans over a large distance or when the computers to be connected to each other are at widely separated locations a local area network cannot be used. A wide area network(WAN) is installed. The communication between different users of WAN is established using leased telephone lines, satellite links and similar channels. It is cheaper and more efficient to use the phone network for the link.

15. PERSONAL AREA NETWORK(PAN) A personal area network is a computer network organized around an individual person. It generally consists of a mobile computer, a cell phone or personal digital assistant. PAN enables the communication among these devices. It can also be used for communication among personal devices themselves for connecting to a digital level network and internet. The PANs can be constructed using wireless or cables.

16. NETWORK ING ARCHITECTURE NETWORK ARCHITECTURE PEER TO PEER NETWORK CLIENT-SERVER NETWORK

17. PEER TO PEER NETWORK In peer to peer network each computer is responsible for making its own resources available to other computers on the network. Each computer is responsible for setting up and maintaining its own security for these resources. Also each computer is responsible for accessing the required network resources from peer to peer relationships. Peer to peer network is useful for a small network containing less than 10 computers on a single LAN . In peer to peer network each computer can function as both client and server. Peer to peer networks do not have a central control system. There are no servers in peer networks.

18. ADVANTAGES & DISADVANTAGES OF PEER TO PEER NETWORK Not very secure No central point of storage or file archiving Additional load on computer because of resource sharing Hard to maintain version control Advantages: Use less expensive computer hardware Easy to administer No NOS required More built in redundancy Easy setup & low cost Disadvantages :

19. CLIENT/SERVER NETWORK In client-server network relationships, certain computers act as server and other act as clients. A server is simply a computer, that available the network resources and provides service to other computers when they request it. A client is the computer running a program that requests the service from a server. Local area network(LAN) is based on client server network relationship. A client-server network is one n which all available network resources such as files, directories, applications and shared devices, are centrally managed and hosted and then are accessed by client. Client serve network are defined by the presence of servers on a network that provide security and administration of the network.

20. Advantages: Very secure Better performance Centralized backup very reliable Disadvantages : requires professional administration More hardware- intensive More software intensive Expensive dedicated software ADVANTAGES & DISADVANTAES OF CLIENT-SERVER NETWORK

21. NETWORK TOPOLOGIES Network topology is the way a network is arranged, including the physical or logical description of how links and nodes are set up to relate to each other.

22. POINT TO POINT TOPOLOGY In a point-to-point connection, a communication link is established between two devices with one wire or air (in the case of wireless). A simple example of point-to- point connection is talking over telephone between two persons where anyone else is not allowed to use the phone on either side.

23. BUS TOPOLOGY In a bus network, a common backbone is connected to all network devices. The high capacity bus backbone (generally a single cable) functions as a shared communications medium and it joins networks and central devices.  If any network device wants to communicate with another network device within a bus network, the device sends a broadcast message onto the backbone. All other devices will see the broadcast message but only the desired recipient will accepts and process the message.

24. STAR TOPOLOGY Star topology is the most popular network topology that is used in many business and home networks today. A star topology is established with a central connection point called a hub node. The hub may be an actual hub device or a network switch or a network router.The main benefit of a star network is that failure in any start network cable will only take down one computer’s network access but not the entire LAN. However, if the hub node fails, the entire network will be down in a start network.

25. RING TOPOLOGY In a ring network, every network device is connected to two neighbor devices with a point-to-point connection for communication purpose. All devices in a ring network make a loop. If any cable or device is fail, the loop will break and also break down the entire ring network. In the ring network, messages travel through the loop in the same direction (effectively either clockwise or counterclockwise).

26. TREE TOPOLOGY The tree topology is also known as hierarchical topology . In a tree topology, a central ‘root’ node (top level of the hierarchy) is connected to one or more other nodes that are one level lower in the hierarchy with a point-to-point physical link. The second level node may also have connected to one or more other nodes that are one level down in the hierarchy with another point-to-point link. The top level node i.e root node is the only node that has no other node above it in the hierarchy.

27. MESH TOPOLOGY In a mesh network, every network device is connected to every other network device with a point-to-point connection. This topology is mostly used in WAN and wireless networks. The route concept is introduced by mesh topology and this topology is used by routers to determine the best path.As each device is connected to all other devices in a mesh network, this topology is the most expensive and difficult to maintain.

28. NETWORK SECURITY Network security consists of the policies and practices adopted to prevent and monitor  unauthorized access , misuse, modification, or denial of a computer network and network-accessible resources . Network security involves the authorization of access to data in a network, which is controlled by the network administrator. Users choose or are assigned an ID and password or other authenticating information that allows them access to information and programs within their authority. Network security covers a variety of computer networks, both public and private, that are used in everyday jobs: conducting transactions and communications among businesses, government agencies and individuals.

29. NETWORK SECURITY Networks can be private, such as within a company, and others which might be open to public access . Network security is involved in organizations, enterprises, and other types of institutions. It does as its title explains: it secures the network, as well as protecting and overseeing operations being done. The most common and simple way of protecting a network resource is by assigning it a unique name and a corresponding password.