what is the wireless definition

Wireless is a technology in a variety of needs can be applied. Wi-Fi is also an alternative technology that is easy to implement in the workplace. Unlike the use of cable, wireless and high-mobility devices on the target moves, while it is in the range of wireless devices.

Wi-Fi is a wireless network and wireless, and only the right tools that can be connected together.
WI-FI technology, the Institute of Electrical and Electronics Engineers (IEEE) is defined:

IEEE 801.11a standard, with a frequency of 5 GHz at speeds of 54 Mbps and 300-meter indoor coverage.
IEEE 802.11b, with a frequency of 2.4 GHz, a speed of 11 Mbps and has 100 meters of the net.
yabg IEEE 802.11g with a frequency of 2.4 Ghz has a speed of 54 Mbps and 300 meters of the net.
IEEE 802.11n is the merger of the two frequencies of 2.4 GHz and 5 GHz (MIMO), can be used with multiple antennas and has a speed of 108 Mbps and reach further.

Wireless type used in wireless LANs

Special is a sample of the combination of two or more computers and other wireless leptop devices on a network drive without using a central data server or as an object. Such networks are very supportive portablelitas seem slow data transmission, especially when used for the use of more than two wireless devices. Networks of this kind is not good and really Bussy, whether the use of multiple devices.
Infrastructure is a model for many devices to integrate wireless devices. This method uses an Access Point, which is used as data centers, so that all wireless devices are connected not connected to each other, but to enter into the center of the device. But to establish the IP address of all computer equipment and must through the middle of the first device. This method has configured a network connection through the heavy and centralized.

Main components of the wireless devices are:

Access Point
Wireless LAN
Wireless Mobile / Destkop

Wireless Security

Output of the signal in a wireless network with the free frequency is transmitted, it can be captured and used by other users of wireless network users. This requires security in wireless media can be used only by the parties correctly. The method of security on wireless security are:

No Secource / Open allows this method mengguanakan all wireless devices can connect to the network, for use in a closed network of networks is very risky, but as the campus and in the office that have no basis comersil centralized data is strongly recommended.
Key actions used, this method allows the most important only authorized users can access the network.

The advantages of wireless networks

Low maintenance costs
Small-scale infrastructure
ApID development
Easy to install and cheap
Supports portability

The weakness of the wireless network

The cost of expensive equipment
Large Deley
no rules on the use of radio frequencies
terinterfensi easily by noise
Network of network capacity is much smaller than the media such as glass fiber
Data security is not guaranteed

If used on a large scale, is a wireless router can be very useful

Source :
www.clearwireless.org

Make WiFi Noise To Breakthrough

A team of Stanford researchers have come up with "full duplex" radios that can talk and listen at the same time -- a feat that enables communications simultaneity over WiFi networks. Cutting through existing WiFi congestion could double network speeds and capacities, encourage ambitious new projects -- such as citywide WiFi -- and even help prevent plane crashes.Ten-4. Back to you. Over.

On a radio or over the TV airwaves, speakers have to rely on back-and-forth communications because radio traffic only flows in one direction at a time on a frequency. Or so said scientific conventional wisdom, until Stanford researchers developed so-called "full duplex" radios that can send and receive signals at the same time. Twice as fast as existing radio devices, the new technology promises less congested, more efficient networks.

"Textbooks say you can't do it," said the technology's principal investigator Philip Levis, assistant professor of computer science and of electrical engineering at Stanford. "The new system completely reworks our assumptions about how wireless networks can be designed."

Dreams of supercharged WiFi connections are already dancing.

"Full-duplex technology like this could literally double the speed of WiFi connections almost overnight," said Jason Katz, founder and CEO of instant messaging and wireless video technology provider Paltalk.com. "This could greatly enhance each and every WiFi user's Internet experience."
WiFi Workaround

Used to telephones and cellular phones, most people don't think about the inability to communicate simultaneously on radio. Perhaps they should, because cellphones route around the problem with expensive technologies whose costs get passed along to consumers -- and make similar fixes unfeasible for wireless networks that often come free, including WiFi.

The idea for communications simultaneity came virtually simultaneously among three Stanford electrical engineering graduate students -- Jung Il Choi, Mayank Jain and Kannan Srinivasan.

They wanted to answer this question: "What if radios could do the same thing our brains do when we listen and talk simultaneously: screen out the sound of our own voice?" Stanford science writer Sandeep Ravindran explained.

Simultaneous talk on a radio can build a Tower of Babel in no time.

"If both people are shouting at the same time, neither of them will hear the other," Levis told TechNewsWorld.

With help from Levis and Sachin Katti, an assistant professor of computer science and of electrical engineering, the grad students had to overcome an intrinsic flaw in radio communications. That is, a radio's own transmissions -- billions of times stronger than anything it might pick up from another radio -- overwhelm incoming signals, Levis explained.

"It's like trying to hear a whisper while you are shouting," he said. Filtering out the noise became the basis for the new solution, which Paltalk's Katz said should encourage further innovations.

"I would think enabling this technology would encourage more WiFi projects designed to blanket large areas such as cities," he told TechNewsWorld. "Networks should be far less congested, and cities would greatly benefit."
Double Time

Sending and receiving signals simultaneously doubles the amount of information sent, Levis said, which means faster home or office networks -- and a boost to air traffic controllers, a high pressure bunch often beleaguered by the demands of skyward communication critical to safety.

Presently, if two aircraft try to call the control tower at the same time on the same frequency, neither will get through. Such blocked transmissions have caused aircraft collisions, Levis said, a problem the new approach would resolve.

Provisional patent in hand, the Stanford group is trying to increase both transmission strength and distance, necessary before the technology is WiFi-ready.

With an instant messaging client that allows users to share video, audio and text with up to 10 people at any time for free, the thought of faster, cheaper networks that allow more people to communicate at once impresses Paltalk's Katz.

However, where the Stanford innovation goes from here depends "largely on how the inventors decide to commercialize it," he explained. "Regardless, it should cause a new cycle of hardware purchasing to enable the technology."

How to Increase Your Wi-Fi Signal

tips and tricks to incares ypur wi-fi signals.

WiFi Killer

Enjoying reading the latest technology news and reviews here on Crave? Hope you're pleased with yourself, because you're killing a tree. Dutch researchers have discovered the sad news that Wi-Fi makes trees sick.

The tree-loving folks of Dutch city Alphen aan den Rijn commissioned the study after finding abnormalities on trees that couldn't be explained by known viral or bacterial infections. Over the last five years, the study found that all deciduous trees in the western world are affected by radiation from mobile-phone networks and wireless LANs.

Over 70 per cent of trees in urban areas in the Netherlands are afflicted by Wi-Fi sickness, displaying significant variations in growth, and bleeding and fissures in their bark. That's compared with just 10 per cent showing symptoms five years ago. Meanwhile, trees in wooded areas remain happy and healthy, untroubled by wireless unwellness.

We've been debating the health issues raised by Wi-Fi since Crave was knee-high to a router, examining contradictory findings way back in 2007. Since then, there hasn't been any conclusive proof whether Wi-Fi is harmful to humans or not.

The Health Protection Agency states that "there is no consistent evidence to date that exposure to radio signals from Wi-Fi and WLANs adversely affects the health of the general population". A small number of people suffer from electromagnetic hypersensitivity -- the symptoms of which include headaches and nausea -- but there's some debate about the degree to which those symptoms are actually caused by electromagnetic fields.

Generally speaking, our exposure to radio signals from Wi-Fi is well below government safety levels, and much lower than from mobile phones, in part because you don't walk around with a router clamped to your ear. You'd have to live in a Wi-Fi hotspot for a year to absorb the same amount of radio waves as you would from a 20-minute phone call, and there's no concrete evidence that mobile phones are bad for you either. If you're worried, just make yourself a hat out of tin foil.

We like trees an' all, but they're no Internet. There's only one thing for it: we'll just have to launch all the forests into space. Right, time to make like a tree and leave.