31-10-2012, 05:20 PM
Computer Networks
Computer Network.ppt (Size: 737.5 KB / Downloads: 61)
Computer network connects two or more autonomous computers.
The computers can be geographically located anywhere.
Features of Networks
Resource Sharing
Hardware (computing resources, disks, printers)
Software (application software)
Information Sharing
Easy accessibility from anywhere (files, databases)
Search Capability
Communication
Email and Message broadcast
Remote computing
Distributed processing
Wireless Networking
A wireless network joins two or more than two computers by means of communication without using any wires.
Wireless network has made a network extremely portable because of digital modulation, adaptive modulation, information compression, and access multiplexing.
It use air as a medium.
The transmission system is usually implemented and administrated via radio waves where the implementation takes place at physical level.
Wireless LAN(Wi-Fi – IEEE 802.11)
It uses for home/office networking.
WLANs provide wireless network contact using radio signal instead of traditional network cabling and built by joining a device called AP through which a user converse with the AP using a wireless network.
It is providing highest data-transfer rate with 802.11 terminologies.
The technology used in WLANs is Spread Spectrum developed by the military offer secure and reliable services.
It offering various benefit for user like mobility, installation speed and flexibility and scalability.
Wireless WAN
WAN is the wireless network that usually covers large outdoor areas.
Developed on 2.4GHz band these systems usually contain access points, base station gateways and wireless bridging relays.
The speed on such network depends on the cost of connection that increases with increasing distance.
The technology could be used for interconnecting the branch offices of a business or public internet access system.
Wireless Network Usage
Radio frequency signals used in a wireless network therefore you can move about and get connection to the network while you are working an outdoor location.
you can send information over the world using satellites and other signals.
Wireless networks make easy of file sharing, the use of printer and other documents with high security.
wireless networks used in emergency services like police department where wireless network utilize to commune significant information speedily.
vital exercise for wireless networks is as a cheap and fast way to be linked to the Internet in regions especially where no source for communication.
Learning is no longer limited by space and time
Pros & Cons of VPN
A VPN is a inexpensive effective way of building a private network.
The relative ease, speed, and flexibility of VPN provisioning in comparison to leased lines makes VPNs an ideal choice.
A VPN can connect multiple sites over a large distance.
It provide strong protection without affecting performance excessively.
The reliability and performance of an Internet-based VPN is not under an organization's direct control.
VPNs require detailed understanding of network security issues and careful installation / configuration to ensure sufficient protection on a public network like the Internet.
VPN products and solutions from different vendors have not always been compatible due to issues with VPN technology standards.