This document provides an overview of basic telecommunications and networking concepts. It defines what a computer network is and common types of networks including local area networks (LANs), wide area networks (WANs), metropolitan area networks (MANs), and personal area networks (PANs). It also discusses network topologies, standards, the internet, intranets, extranets, and virtual private networks (VPNs).

1. Basics of Telecommunications and Networking

2. Lecture Plan Network Architecture Network standards and open systems Virtual private network Network management system

3. Networking A network is a group of interconnected systems which share services and interact with each other by means of a shared communication link. These systems can be located anywhere. Network is often classified according to its geographical size.

4. Classification of Network The most common classifications of networks are: Local Area Networks (LAN) Wide Area Networks (WAN) Metropolitan Area Networks (MAN) Personal Area Networks (PAN)

5. Computer network connecting computers and other devices in a workgroup, department, building or campus. Local Area Networks

6. Connects BNs and MANs and are usually leased from inter-exchange carriers. Typically span hundreds or thousands of miles. Supports data rates of 28.8 Kbps to 2 Gbps. Wide Area Networks

7. Wide Area Networks

8. Metropolitan Area Networks Is a telecommunication network that connects users and their computers in a geographical area This area is larger than covered by a LAN but smaller than covered by WAN. E.g City or college campus

9. A network that supports the interconnection of information technology within a range of 33 feet or so. Personal Area Networks

10. You may be connected through: Satellite Dial-up Leased line RF Link

11. What is Internet? The Internet is “The Network of Networks” Internet is like a phone system which connects( almost anywhere in the world), Exchanges information Acts as Global link between regional networks Allows unrestricted access 3. Used for Communication through email, Chatting News groups, Files transfer Documents, data (multimedia )sharing etc

12. Internet: An Illustration

13. Internet Media Finance Computers Real Estate Education Health Government Universities Business Server User Client Model of Internet Setup

14. Email application Client Server Client Email client sends message to server Message is stored on POP server Later, recipient’s email client retrieves message from server

15. Internet Publicly accessible network of interconnected computers which communicate via software protocol standards Easily accessed (via modem and phone line, ISDN, direct cable landline, satellite) Expanding global infrastructure

16. Intranet It is an internal corporate network built using Internet and World Wide Web standards and products. It is used by employees to gain access to company information

17. Extranet A network based on web technologies that links selected resources of a company’s intranet with its customers, suppliers, or other business partners.

18. To summarize Yes Business partners Extranet Yes Employees & Managers Intranet No Anyone Internet Need of user id and password Users Type

19. Virtual Private Network It is used for secure intranet and extranet access applications. A VPN is a secure connection between two points across the Internet.

20. VPN - Layout Tunnel ISP ISP Firewall (data Encoded) Firewall (data Encoded) Sending Computer Receiving Computer

21. Computer Network topology A communications network is two or more computers connected to share data and resources are “networked.” The simple idea behind computer networking is to allow users to access more information and give them access to devices not directly attached to their “local” system, such as printers or storage devices.

22. Computer Networks Network connections can also be made using RADIO transmission – Wireless. Allows user to stay connected to their home/office network using portable PC or PDA or may be Cell phone. Two Technologies that use wireless networking – Bluetooth (for home or small office use) and wireless Ethernet.

23. Local Area Networks- 3 basic topologies These are either the logical or physical way the computers are connected. Each connection on the network is known as a node . These topologies are: Star Bus Ring Mesh [ Partially connected, Fully connected ] Tree

24. A Star topology connects all the nodes directly to the server or to a connecting device such as a hub .

25. All nodes on a Bus topology are connected to a central line or backbone.

26. Nodes on a Ring topology are connected in a closed loop. This means that each node has two connections, one in and another out. Using this type of topology the data must travel through all the nodes.

27. Thank You…. Help is available !