A computer network connects computers and devices using wired and wireless communication channels. It allows for sharing of resources and information. Wired networks use physical cables to connect devices, while wireless uses technologies like terrestrial microwave, communication satellites, and wireless LANs. Computer networks can be classified based on their physical extent, such as local area networks (LANs), wide area networks (WANs), and metropolitan area networks (MANs), which connect devices within a building, across cities, and within a city, respectively. Virtual private networks (VPNs) extend private networks over public ones.

1. COMPUTER NETWORKSubmitted ByGaurav Gupta IILM- Business SchoolMBA July 2011Wednesday, July 06, 20111

2. What is Computer Networking ?A computer network is a collection of computers and devices interconnected by communications channels(wire & wireless) Purpose—To facilitate communications and allow sharing of resources and information among interconnected devicesWednesday, July 06, 20112

3. COMMUNICATION MEDIUMWednesday, July 06, 20113Wired Communication MediumWireless Communication Medium

4. WIRED COMMUNICATIONWednesday, July 06, 20114

5. WIRELESS TECHNOLOGIESTERRESTRIAL MICROWAVE – Terrestrial microwaves use Earth-based transmitter and receiver, like BTS(Base Trans-receiver Station)Wednesday, July 06, 20115

6. WIRELESS TECHNOLOGIESCommunications satellites -- The satellites are stationed in space, typically 35,400 km (22,200 miles) (for geosynchronous satellites) above the equator. These Earth-orbiting systems are capable of receiving and relaying voice, data, and TV signalsWednesday, July 06, 20116

7. WIRELESS TECHNOLOGIESWireless LANs – Wireless local area network use a high-frequency radio technology similar to digital cellularWednesday, July 06, 20117

8. WIRELESS TECHNOLOGIESA global area network (GAN) is a network used for supporting mobile communications across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off the user communications from one local coverage area to the nextWednesday, July 06, 20118

9. NETWORKS CLASSIFIED BY THEIR PHYSICAL OR ORGANIZATIONAL EXTENT Local area network (LAN),Wide area network (WAN),Metropolitan area network (MAN),Personal area network (PAN),Virtual private network (VPN),Campus area network (CAN),Storage area network (SAN),Controller area network (CAN).Wednesday, July 06, 20119

10. VPN (Virtual Private Network)Share Brokerage FirmWednesday, July 06, 201110

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