1. Lesson 3 – UNDERSTANDING NETWORKING

2. Network relationship types Network features OSI Networking model Network hardware components OVERVIEW

3. Peer-to-peer Client / server NETWORK RELATIONSHIP TYPES

4. Computers on the Network communicate with each other as equals. Peer-to-peer relationships

5. Each computer: Shares resources. Sets up and maintains security. Accesses Network resources. Peer-to-peer relationships

7. A distinction exists between computers that make available Network resources and computers that use those resources. Client / server relationships

8. Resources are centrally managed and hosted. Client computers do not share resources with other client computers / servers. Server computers make available, manage, and administer shared resources. Client / server relationships

10. Use less expensive hardware. Easy to administer. No NOS required. More built-in redundancy. Pros for Peer-to-peer Networks

11. May hurt user’s performance. Not very secure. Hard to back up. Cons for Peer-to-peer Networks

12. Very secure. Better performance. Centralized back up. Very reliable. Pros for Client / server Networks

13. Require professional administration. More hardware intensive. Cons for Client / server Networks

14. File sharing Printer sharing Application services E-mail Remote Access Wide Area Network Internet and intranet Network security NETWORK FEATURES

15. Originally, the primary reason to have a Network. Provides central storage for common documents, databases, and work files. Requires a shared directory or disk drive. Incorporates File Locking. File sharing

16. Most common ways of sharing printers are: Printer queues. Workstations that access printers directly. Printer sharing

17. Printer server function can be filled by: A fileserver with the printer connected to it. A computer connected to the Network, with the printer connected to the computer. An in-built print server on a printer’s NIC. A dedicated Network print server. Printer sharing

18. Advantages: Reduces disk space needed. Easier to administer the application. Application services

19. E-mail systems are divided into: File-based. Client / server. E-mail

20. File-based e-mail system: Consists of a set of files kept in a shared location on a server. E-mail

21. Client / server based e-mail system: Contains messages and handles e-mail interconnections, inside and outside the company. E-mail

22. Users use this feature to access files and e-mail from a remote location, such as their homes. Remote Access

23. Methods: Set up Remote Access Service (RAS) connection on a Windows NT server. Use a dedicated RAS. Employ a workstation on the Network. Set up a Virtual Private Network (VPN). Install Windows Terminal Server or Citrix MetaFrame. Remote Access

24. WAN is the connection of multiple Local Area Networks (LANs). It is created when users of one LAN need frequent access to the resources on another LAN. Wide Area Network

25. An Internet connection for a Network consists of a telecommunications network connection to an Internet Service Provider (ISP). Internet and intranet

26. Network components : Leased 56KB line ISDN line, or a fractional or full DS1 (T-1) connection Channel Service Unit / Data Service Unit (CSU/DSU) Router Firewall Web server Internet and intranet

27. This internally focused Network: Mimics the Internet. May also host Internet-type services like FTP servers. Is not usually accessible from outside the LAN. Internet and Intranet

28. Provided by: Features of the NOS. Physical cabling plant. The Network’s connection with other Networks. Client workstations. Actions of the users. Security policies. Etc. Network security

29. Conceptual model. Used in Network design and engineering Network solutions. Defines methods and protocols needed to connect one computer to another. OSI NETWORKING MODEL

30. The 7 layered OSI Model

31. 7 layers of the OSI Model Defines the properties of the physical medium used to make a Network connection.

32. 7 layers of the OSI Model Connection can be either: Point-to-point Multipoint Transmission can be either: Half-duplex Full-duplex

33. 7 layers of the OSI Model Defines standards that assign meaning to the bits carried by the physical layer.

34. 7 layers of the OSI Model This layer is sub-divided into: Logical Link Control Medium Access Control

35. 7 layers of the OSI Model Defines how data packets get from one point to another on a Network and what goes into each packet.

36. 7 layers of the OSI Model Manages the flow of information from one Network node to another.

37. 7 layers of the OSI Model Defines the connection from a user to a Network server or from a peer on a Network to another peer.

38. 7 layers of the OSI Model Takes the data supplied by the lower-level layers and trans- forms it so it can be presented to the system.

39. 7 layers of the OSI Model Controls how the operating system and its applications interact with the Network.

40. How data travels through the OSI layers

41. Servers Hubs, Switches, and Routers Cabling and Cable Plants Workstation Hardware NETWORK HARDWARE COMPONENTS

42. A server is any computer that performs Network functions for other computers. Servers

43. Types of servers: File server. Print servers. Application servers. E-mail servers. Networking servers that provide Network services (automatic assignment of TCP/IP addresses). Servers

44. Types of servers: Routing servers (routing of packets from one Network to another). Web servers (encryption/decryption and other security services). Virtual Private Network (VPN) servers. Internet servers. Remote Access servers. Servers

45. Typically run some Network Operating System (NOS) like: Windows 2000 Server and Advanced Server Windows NT Server Novell NetWare UNIX Servers

46. A true server-class computer will have: Built-in redundancy with multiple power supplies and fans. High-performance designs. Monitoring software and hardware. Servers

47. A hub (concentrator) connects a number of network cables to a Network. Network connections on a hub share a single collision domain. Hubs, Switches, and Routers

48. A typical Network hub Hubs, Switches, and Routers

49. A switch makes a Network connection private. It collects data from each connection and forwards it to a Network backbone. Switches connect many hubs to a single backbone. Hubs, Switches, and Routers

50. Using switches and hubs in concert Hubs, Switches, and Routers

51. A router routes data packets from one Network to another. Two Networks connect to a router using their own wiring and connection type. Hubs, Switches, and Routers

52. Types of Network cable: Unshielded Twisted Pair (UTP) Shielded Twisted Pair (STP) Coaxial Cable (coax) Fiber Optic Cabling and Cable Plants

53. Any computer on a Network is referred to as a Network workstation (or Network Client). Workstation Hardware

54. Network relationship types: Peer-to-Peer networks Client / server Networks SUMMARY

55. Network features: File sharing Printer sharing Application services E-mail Remote Access Wide Area Network Internet and intranet Network security Summary

56. Open Systems Interconnect (OSI) Networking Model: Application Presentation Session Transport Network Data-link Physical Summary

57. Network Hardware Components: Server types Hubs, Switches, and Routers Summary

58. Cabling and the Physical Plant: UTP STP Coax Fiber Wireless Summary