1. Networking Basics Lesson 1 Introduction to Networks

2.  What is Networking?  Networks Environments  Standalone Networking  LANs Vs WANs

3. Network definition  data network is a group of computers connected by a network medium.  The network medium carries signals between computers.  Signals reduce complex information to the simplest possible form.  Computers communicate by using a language called a protocol.

4. Protocol Services  Packet acknowledgment  Segmentation  Flow control  Error detection  Error correction  Data compression  Data encryption

5. Networks Environments  Standalone

6. Networks Environments  Networking

7. Networking Benefits  Sharing Resources  Information  Hardware  Software  Fault Tolerance  Protecting Information  E-mail

8. Network Primary Types  Local Area Networks (LANs)  Wide Area Networks (WANs)

9. LAN  local area network (LAN) is a collection of computers located in a relatively small area and connected by a common medium.  The pattern in which computers in a LAN are connected is called the topology.  LAN topologies include bus, star, and ring.  The defining protocols for a LAN are the data- link layer protocols.

10. Wide Area Network A WAN uses an external network provider to connect LANs.

11. Example of WAN network

12. EX. Of WAN Frame Relay  A packet-switching protocol for connecting devices on a Wide Area Network (WAN)  Frame Relay networks support data transfer rates at T-1 (1.544 Mbps) and T-3 (45 Mbps) speeds  Most telephone companies now provide Frame Relay service for customers who want connections at 56 Kbps to T-1 speeds

13. ATM  Short for Asynchronous Transfer Mode  technology based on transferring data in cells or packets of a fixed size  Creates a fixed channel, or route, between two points whenever data transfer begins (Point to Point)  Needs special ATM Device in both network, sending & receiving  Rarely used

14. A backbone network connects segments together, forming an internet work.

15. Administrator Responsibility  Security  Resources Administrating  Applications & Data Maintaining  Installation & upgrading

16. Network Requirements  Connections (NIC, Medium)  Communication (Protocol)  Services

17. Roles of Computers in a network  Clients  Request Only  Servers  Reply to Requests Only  Peers  Request & Reply

18. Network Types  Peer to Peer  No Dedicated Server  Server Based  Dedicated Servers & Clients Centralized  Dump Terminal

19. Peer to Peer Network  Workgroup  No Central Logon (Local Account) No Specific OS

20. Advantages of Peer to Peer  No Extra Investment for Hardware or Software  Easy Setup  No Administrator required  Users control what to share  No reliance on other computers  Lower Cost for small networks (10 users)

21. Disadvantages of Peer to Peer  Additional Load on PCs  Inability to handle many network connections as servers  Lack of Central Organization  User should administer their own computers  Weak security

22. Server Based Networks  Domain Model  PDC/BDC  Active Directory

23. Advantages of Server Based Networks  Strong Security  Central File Storage  Share Expensive Equipment  Dedicated Servers are optimized for their job  Users don’t bother managing the network

24. Advantages of Server Based Networks [Cont.]  Single Password allows access to all shared resources depending on permissions  Central organization  Easy Manageable for large numbers of users

25. Disadvantages of Server Based Networks  Expensive Dedicated Hardware  Expensive Network OS  A dedicated Network Administrator

26. Centralized Network  Using Dump-Terminal

27. Server Types  File & Print Server  Database Servers (Application Server)  Mail Servers  Fax Servers  Directory Service Server (Active Directory)