A wireless network is one that totally discounts the use of wires to interconnect between, or digital devices. It uses radio waves to receive and transmit data. Wireless personal area network is a type of wireless network. It is used in interconnecting devices within a relatively small are, usually within a person's reach. Examples include Bluetooth radio, infrared. Wireless local area network is another type of wireless network. It interconnects devices over a relatively short distance, with an area of coverage wider than that of wireless personal networks. It serves dual purpose. It can either be used to interconnect devices to one another or on the other hand, used to connect to the internet through a wireless access point.
The radios transmit at frequencies of 2.4 GHz or 5 GHz; this is at a frequency higher than that used in walkie-talkies and televisions. This confers the advantage that more data can be transmitted. Wireless radios work by converting binary data in the form of 1s and 0s into radio signals which is transmitted into receivers that also convert the radio signals back to the corresponding binary code.
Several standards are which are in use are defined by the Institute of Electrical and electronics Engineers (IEEE) in the order of 802.11. They include 802.11a, 802.11b, 802.11g and 802.11n. The 802.11a transmits data at a speed of 5 GHz and can achieve a data transfer rate of 54 megabits of data per second. It uses the coding technique referred to as the Orthogonal frequency-division multiplexing (OFDM) to encode the signal before it reaches the receiver.802.11b is popular for being inexpensive. However, this is at the expense of speed. It transmits data 2.4GHz and can transmit data at the rate 11 megabits per second. It also uses the coding technique called Complementary coding keying (CCK) modulation to greatly improve on speed. 802.11g transmits at a 2.0 GHz but is a lot faster, unlike the 802.11b. It can transmit up to 54 megabits of data per second.
Essentially, the workings of DHCP, DNS and Active Directory work the same way. The major difference is in the function of the DHCP which automatically assigns IP addresses to devices on the LAN. It is better to disable this function on the wireless network so as to prevent unauthorized access to the network. If DHCP is activated, then, any computer that joins the networks is automatically assigned an IP address and so, is able to utilize resources on the network. If DHCP is disabled, then the administrator adds individual devices onto the network. This way, unauthorized access is prevented
In utilizing a wireless network, several threats to security are encountered. They include, but are not limited to: unauthorized access to broadcasted data. There is always a possibility that data transmitted across a wireless network is intercepted by a third party which can have disastrous effects. This danger is averted by encrypting the data. The WPA/WEP encryption solves this problem. With encryption, the information sent over the network is scrambled so that it is extremely difficult for a third party to interpret the information, even if it is intercepted.
There is always the danger of unauthorized utilization of the wireless network by outsiders that are not registered members of the network. This problem is compounded by some hardware vendors reconfiguring access points and routers with a default SSID. If a hacker finds this out, they may have the impression that the particular network is poorly configured and attack such. This problem can be solved by changing the default SSID and password on such hardware.
For the deployment of wireless networks in a global multi-site organization,
An intranet is created in the organization using a Wireless Access Point. This is used to interconnect devices in that particular location.
A VSAT can be used to provide internet connectivity with various intranets.
The VSATs can be linked up by Satellite communication across the world.
A WiMax network can also be used to interconnect several intranets within a city.
Virtual private networks allow private data to be transmitted across the internet using the internet as the public infrastructure. VPNs allow an individual to access an intranet network from a remote location. Moreover, it also allows multiple intranets to be interconnected within an organization. VPNs also allow several networks to be interconnected among several organizations, forming an extranet.
With these capabilities, a VPN can be used to interconnect devices within an organization in a particular location it also offers possesses the ability to interconnect computers in the same company but at different locations. Also, VPNs can also allow several organizations to interconnect their devices for the purpose of data exchange. In all, VPNs are ideal for global companies that have branches in different locations, even at different parts of the world. Also, it allows a user to access their information from remote locations.
VPNs work based on the client/server model. The VPN client is the end user and it allows remote connection by that device to be connected via a VPN server to another network.
