1 - Understending Local Area network (1).pptx

Presetagion about computer networks

1. Understanding Local Area Networking

2. Objective

3. Network components and Terminology Data Node Client Server Peer Network adapter Hub Switch Router Media Transport Protocol Bandwidth

4. What does network administrator works? Your opinion on network expansion? What do you think about working as network administrator? Does it have potential or not? D iscussion

5. Networks Sharing Communication Organization Money

6. Network infrastructure The network infrastructure contains three categories of network components:

7. Media

8. Services

9. Circuit based vs packet switching networks

10. Types of network Local Area Network (LAN) Wide Area Network (WAN) Other types of networks include: Metropolitan Area Network (MAN)  Wireless LAN   (WLAN)  Storage Area Network (SAN) Personal Area Network (PAN)

11. Local Area Network A Local Area Network (LAN) is group of computers confined to a small geographic area, such as a single building A LAN is a group of computers or devices that share a common communication medium, such as cabled or wireless connections

12. Basic example of LAN Broadcast

13. SOHO – small office-home office

14. More advence example of a LAN

15. Network Documentation Network documentation helps describe, define, and explain the physical and logical method for connecting devices The documentation phase occurs before a network is built, or when changes are made to the network Microsoft Visio is a tool that can be used to document networks

16. HUB A Hub is the most basic central connecting device Hubs enable computers on a network to communicate A host sends data to the hub. The hub sends the data to all devices connected to the hub

17. Switch Switches work the same was as a hub, but they can identify the intended recipient of the data Switches can send and receive data at the same time

18. How Switch works https:// www.youtube.com / watch?v = ByyjLbmmHW4

19. Router Routers enable computers to communicate and allow communication between two networks – such as your home network and the Internet This communications link between the one network and the other is where the LAN ends

20. Network adapter Network interface card or NIC is the device that enables you to send and recive dato to and from computer

21. NIC RJ45 port or 8P8C

22. RJ45 plug

23. Twisted Pair Cable Standard Twisted Pair Cable Shielded Twisted Pair Cable

24. Network adapter Computer management

25. Properties windows of an Intel network adapter

26. Link speed of network adapter full duplex half duplex Transcive

27. Properties windows - Windows 10

28. LAN Connection Properties dialog box TPC/IPv4 TPC/IPv6

29. LAN status Type of connectivity Speed Time Total bytes send Total bytes received

30. Logical and psychical address Every computer on LAN has psychical and logical address.

31. Defining data transfer on a LAN Information is send from one network adapter to another Serial data transfer means the transfer of one bit at a time

32. Ethernet Institute of Electrical and Electronics Engineers (IEEE) standard (802.3) that defines how information is sent and received between network adapters, hubs, switches, and other devices Ethernet is the de facto standard and is the most widely-installed local area network technology Common types of Ethernet include: 802.3u or Fast Ethernet that runs at 100 Mbps 802.3ab or Gigabit Ethernet

33. Metcalfe's first Ethernet sketch This diagram was hand drawn by Robert M. Metcalfe and photographed by Dave R. Boggs in 1976 to produce a 35mm slide used to present Ethernet to the National Computer Conference in June of that year. On the drawing are the original terms for describing Ethernet

34. Broadcast, Multicast, Unicast Broadcast – all to all communication Multicast -  is group communication Unicast – one to one communication

35. Frames Computers on Ethernet networks communicate via frames A frame is a sequence of bits containing a detectable beginning and end of a packet in the stream of bits A frame is a data packet residing on Layer 2 of the OSI model data frame crc (4 bytes) preamble (8 bytes)

36. IP packets

37. Data transfer on a LAN 1. Data is packaged by operating system info packet 2. Network adapter takes the packet and places it in inside frame 3. Now, the frame of information need to be sent to the physical media – cabling. To do this, the network adapter breaks down the frame of information into a serial data streem that is send one bit at a time across the cables to the other computer 4. The reciving computer takes the single-bit stream and recreate the frame of data and create packet 5. Packet is send to the operating sistem

38. Internet Protocol - IP IP address Subnet mask

39. Host The fact that a device or computer has an IP address is what makes it a host

40. Internet Protocol Version 4

41. Command ipconfig

42. Command ping

43. Identifying Types of LANa Types of LAN: - Wired connections - Wireless connection - Mix - Virtual LANs

44. Wired LAN Computers and other devices are wired together using copper-based twisted-pair cables. Hubs, switch, routers

45. Wired LAN diagram

46. Wireless LAN Wireless local area network (WLAN) Wireless access point (WAP)

47. Wireless LAN diagram

48. Virtual LAN - VLAN A virtual LAN is a group of host with a common set of requirements that communicate as they were connected together in a normal fashion on one switch, regardless of ther physical location.

49. FRAME

50. Example of port-based VLAN

51. Perimeter network DMZ – demilitarized zone Back-to back configuration 3-leg perimeter configuration

52. Back-to back configuration

53. 3-leg perimeter configuration

54. Network Topologies A network topology defines the physical connection of host in a computer network.

55. Star topology Most Common topology Each computer is individually wired to a central connecting device (hub, switch or SOHO router) with twisted-pair cabling

56. Mesh topology Every computer connects to every other computer; no central connecting device is needed.

57. Ring topology In a LAN environment, each computer is connected to the network using a closed loop Used by Token Ring and Fiber Distributed Data Interface (FDDI)

58. It's All About IEEE 802.3™ Ethernet

59. Ethernet standards

60. IEEE 802.3 (  Institute of Electrical and Electronics Engineers ) CSMA/CD ( Carrier-sense multiple access with collision detection )

61. Collision detected procedure If a collision was detected in step 4

62. In the topology above we have a hub network. Host A is trying to communicate with host B. Host A “senses” the wire and decides to send packets. But, in the same time, host C sends its packets to host D and the collision occurs. The sending devices (host A and host C) detect the collision and resend the packet after a random period of time. NOTE Since switches are now commonly used in networks instead of hubs, CSMA /CD is not really used anymore. Each port on a swich usually operate in a full duplex mode and there are no packet collisions in a full duplex mode.

63. Collision & broadcast domain Collision domain

64. A broadcast domain is the domain in which a broadcast is forwarded. A broadcast domain contains all devices that can reach each other at the data link layer ( OSI layer 2) by using broadcast.

65. Centralized Computing Computing is done at a central location using terminals that are attached to this main system Mainframes are a powerful computer and the rest of the devices connected to the computer are known as terminals (or dumb terminals) Each terminal consisted solely of a keyboard and display with no processing power

66. Client/Server Model The client/server model is an architecture that distributes applications between servers and client computers Server: System that provides services such as Windows Server 2008 R2 Client: Device that requests services such as Windows 7

67. Example of uses for server File server Print server Database server Network controller Messaging server Web server CTI-based server

68. Peer-to-Peer Networking Peer-to-peer networking distributes applications or workloads between computers Peers are both service providers and service requestors

69. Distributed Computing Distributive computing includes both client-server and peer-to-peer networks Every device or workstation has its own processing power