The basic system of WiFi is very simple. In a WiFi enabled network, computers with WiFi cards connect wirelessly to an access point or router. This access point or router is internet enabled the usual way, connected to the internet using a cable or DSL modem. Any PC or laptop with a WiFi card, which is within a radius of 200 feet (60 meters) from the access point can access internet. However a distance of 100 feet (30 meters) is considered ideal for good quality access. An area surrounding an access point, providing wireless access, is called a wireless hotspot.
The Technology
The technology used in WiFi is easiest to understand in terms of radio. An ordinary walkie-talkie can handle only limited data in the range of 1000 bits per second, and operate at 49 MHz. In the case of WiFi radios, the signal strength is much more, so they can handle much higher data rates. WiFi radios typically operate at a frequency of 2.4GHz.
There are three versions of WiFi radios currently available- the ones that work with 802.11b, 802.11g and 802.11a standards. While the first two- 802.11b and 802.11g- transmit 2.4 GHz, the radios operating at 802.11a standard can transmit at 5GHz.
Another important feature of the WiFi radios that enables higher data rates is the coding techniques used. The 802.11a and 802.11g standard radios use Orthogonal Frequency-Division Multiplexing (OFDM) technique while the 802.11b uses Complementary Code Keying (CCK) technique.
Due to the higher frequencies and the encoding techniques, WiFi radios can transmit a very high amount of data per second. The 802.11a and 802.11g standard radios transfer between 30-54 megabits per second and the 802.11b standard typically conveys 7-11 megabits per second.
The WiFi Alliance has developed certification standards for laptops and other electronic gadgets like PDAs. Most of these appliances are today WiFi certified. The Benefits
The technology of WiFi was developed to enhance the convenience and increased productivity that portable computing and communication systems ushered in. In today's scenario, the workforce moves about a lot on business. They typically carry laptops, PDAs and other gadgets and need to access the office network from wherever they are. WiFi is a hassle-free, cost effective and quicker way of deploying a network. A WiFi enabled work environment helps workers to stay connected for longer and even interact with the co-workers effortlessly.
A wireless access point has the risk that anyone can access the information if they get within an accessible distance. Therefore it is important to take security precautions while setting up a WiFi network in your organization. The degree of security depends on the nature of information your organization handles. If it is highly sensitive information, you will need to go for customized security measures.
WiFi, or Wireless Fidelity, is a technology standard developed in 1997 by the Institute of Electrical and Electronics Engineers (IEEE). WiFi is all about high speed wireless internet access. In today's scenario, workers typically move about a lot and need to operate from several stations other than their office cabin. As gadgets like laptops and PDAs were developed to meet this need, it was also necessary to develop wireless internet technologies to enhance their function. This is where WiFi comes in.
WiFi is Fast
WiFi typically offers much faster internet access than cable and DSL connections, a definite advantage for businesses. WiFi is Convenient
You can access internet from your Wi-Fi enabled device from wherever you are, as long as you are within range of a base station or source. Thus the workers can move about with their gadgets from their cabin down the corridor to the conference room all without losing connection. You can also access your company's network from your own laptop or PDA, even when you are in another place, like a business associate's office, a hotel or convention center, as long as this place has a WiFi network.
It is also faster and more cost effective for the company to set up a wireless network than a wired connection.
WiFi is Ubiquitous
The WiFi technology is already commercialized, so most of the computing and communication gadgets like laptops and PDAs come WiFi enabled. Further, these WiFi certified gadgets are interoperable regardless of the brand.
On the other hand, public WiFi access sites or hot spots are also on the increase. More and more offices, bookstores, airport lounges and food outlets are setting up WiFi hotspots in the hope that this will induce their tech-savvy customers to stay on. In some cities, entire neighborhoods and business districts are setting up bigger hotspots.
Drawbacks
The small range is the biggest drawback for WiFi. Most typically, it is about a radius of 100 feet or so from the hotspot.
Earlier versions of WiFi radios drain a lot of power, which is a disadvantage for laptops as they are battery dependent. Also, nearby equipment like microwave ovens and cordless phones can cause interference.
Security is another big threat. It is easy for anyone to access your wireless networks if you are not careful. Therefore it is important to install stringent security precautions depending on the sensitivity of the information you handle.
Wi-Fi Internet
WiFi uses radio technology for communication, and mostly operates at 2.4 or 5 GHz frequency. Most of the new connectible devices are today WiFi certified, which means not only that they are WiFi enabled, but also that these devices are interoperable.
In a WiFi network, computers with a WiFi network card can connect wirelessly to a WiFi router. The router is connected to internet using a cable or DSL modem. Any WiFi enabled connectible device within 60 meters or so of the access point can access the internet.
Some WiFi hotspots are open in the sense that anyone with a connectible device within the range can access them, while some others are closed which means that only authorized users can access them using a password.
Where WiFi can Help
Interoperability is one big advantage of WiFi. WiFi allows users to connect with internet as well as with each other and other devices. WiFi technology is of special advantage to people in marketing and sales as these sectors involve a lot of travel. In fact WiFi can help anyone who has to move about a lot on work. They can access their work email or company databases from wherever they are using WiFi technology. Thus WiFi technology allows businesses to grow and expand fast.
Further, businesses do not have to throw away their existing network infrastructure to start on WiFi. It is very easy to integrate WiFi into your current wired network. This gives WiFi a definite cost advantage.
As we saw earlier WiFi technology uses the 2.4-5 GHz bandwidth and speeds ranging from10 to 50 Mbps. Security
All said and done, security is one of the biggest issues with a wireless network. This is all the more relevant in the case of a plug and play technology like WiFi. Security is also applicable when you need to access a public hotspot using your laptop or other devices.
Wi-Fi Phones
A WiFi phone is a wireless device that gives you the dual benefits of wireless connectivity and the cost savings of VoIP. It can be used in any areas- hotspots- where WiFi connectivity is provided. If there are no obstructions, you will be able to use a WiFi phone within a radius of 300 feet (90 meters) of the hotspot. However this also depends on the number of people accessing the hotspot at the given moment.
What a WiFi Phone Can Do
Just like a cell phone, you can use a WiFi phone to make calls, send text message, receive voicemail and to some extent even access the internet. The WiFi phone is capable of retrieving data and accessing the internet better than a cell phone.
As wireless hotspots are becoming widespread, a WiFi phone enables you to converse with your family, friends and work associates anywhere in the world at much cheaper rates than a regular telephone allows. All you need to ensure is that you are within the range of a WiFi hotspot.
In other words, you can use your WiFi phone from home, hotels, offices, airports, internet cafes, business districts or just about anywhere there is a WiFi network established. More and more metropolitan areas and commercial outlets are deploying free or low cost WiFi hotspots, so you have many places where you can use your WiFi phone to make and receive calls.
Most of the WiFi phone models available in the market have built in features like echo cancellation, lost packet recovery and packet delay compensation. Thus you can expect excellent voice quality from WiFi phones.
The Hitch
The problem with WiFi technology is the range and this applies to WiFi phone as well. It is not possible to roam beyond the hotspot, or between two hotspots, and this means limited mobility while you are on a WiFi call. Further, many WiFi enabled phones shut off the WiFi receptor when not in use, in order to save energy. The Bottom Line
The cost effectiveness is the biggest factor here. The average American user today spends $50 a month on cellular calls. Hotspots are free or much cheaper in comparison, and multiplying fast too. By switching over to WiFi phones, the average consumer as well as businesses can save a lot on the telephone bill. From this angle, WiFi phone looks like the next big thing in the telecom revolution.
A New aspect in networking
WiFi has brought a new aspect in the ground of networking. The broadcast of data is completed via radio waves and the cost of cables for network lying down.Wi-Fi enable a user to get access to internet anywhere in the given location. Now you can make a network in Hotels, Libraries, colleges, universities, campus, private institutes, and coffee shops and even on a public place to make your business more profitable and connect with their client any time. WiFi makes waves for business with their highly effective cable less media.
Unmatched mobility and elasticity
Wi-Fi, is allowing new intensity of connectivity without giving up functions. Wi-Fi introduced various types of utilities such music streamers that transmit your music to speakers without any wire you can also play music from the remote computer or any other attached to the network. Wifi technology system is rather remarkable, you can download songs, send email and transfer files expediently at sky-scraping speed and you can move your computer easily because your WiFi network has no cable to disrupt your work so we can say that it is quite easy, helpful and most of all expedient.
Fortress Technology
WiFi providing secure wireless solutions support the growth and release of a prototype mobile ad hoc wireless network for use in the wireless strategic skirmish.
Support an entire age bracket.
WiFi technology has several advantages it support an entire age bracket and create a connection between components on the same network and have ability to transfer data between the devices and enable different kind of devices such as game, MP3 player, PDA's and much more!
It's convenient and every where
WiFi is a convenient technology and where the range station exists you are online during travel you can equip with a Wi-Fi network and set up shop anyplace. You will automatically connect with internet if you are near hotspot. These days WiFi exist every where with all its wonders.
More faster and secure
With WiFi you can get high speed of internet because it is very fast than DSL and Cable connection you can establish a Wifi network in small space now you don't need any professional installation just connect to a power outlet with an Ethernet cord, and start browsing. WiFi security system for Threats makes it more renewable and its tool protect your VPN and secure web page. You can easily configure the device to take better performance. The standard devices, embedded systems and network security make it more powerful
WiFi with no limitation
You can use a "WiFi" network with no limitation because it can connect you worldwide. You can easily reach to your requirements with WiFi networking applications because the power consumption is very high as compared to other bandwidth. The vision of wireless network is bright with Pre-N products and high qulaity media streaming.Further details are available on Wifi
Philadelphia, the city of brotherly love has it. Wireless broadband Internet access (WiFi) seems too good to be true. At
relatively low cost, anyone can get on the Internet anywhere in a city. All the city
needs to do is install WiFi antennas.
An argument in favor of citywide WiFi is that it will reduce the digital divide:
the poorer you are, the more limited your access to the Internet and its information
resources. Cities like Philadelphia and San Francisco are actively trying to close the
digital divide. One option is WiFi.
Yet in weighing the options, virtually nothing is heard about the potential health
risks. Saturating an entire city with WiFi adds to the existing burden of nonionizing
radiation. That burden, called electrosmog by some, consists of long-term
exposure to low-level concentrations of nonionizing radiation from familiar sources
like radio and TV signals, electronic and electrical devices, and the ubiquitous cell
phone.
Wireless Internet Access
Local area networks (LANs) link computers, printers, modems, and other
devices. Traditional LANs make the links physically using wire cable. Messages
between computers and the other devices on the network are managed by a device
called a router.
A wireless LAN does away with the wire cable by using a router that transmits and
receives radio signals. To use a wired LAN, you have to plug the computer or other
device into a wall socket. A wire leads from the socket to the router, which manages
signal traffic between the devices on the network.
With a wireless LAN, each device on the network is built so that it can send a signal
to the router and receive signals back. The range can be increased by adding a booster
that increases the signal strength.
As with all radio signals, the closer you are to the transmitter (the router) the
stronger the signal. Cell phones work on the same principle. The difference is that
cell phones work at a different frequency and put out a stronger signal than wireless
LANs.
Radio Frequencies
Cell phones operate at frequencies in the 3 to 30 GHz range, similar to microwave
ovens. Wireless LANs operate at one tenth of that range--0.3 to 3 GHz, the range of
UHF television broadcasts. GHz stands for gigaHertz, a standard measure
of radio frequency radiation (RFR)--electromagnetic radiation created by
sending an alternating electrical current through an antenna. The higher the GHz,
the faster the current alternates.
Frequency by itself does not measure the potential effect of RFR. As you would
guess, the strength of the signal also matters. The strength of a signal is measured
in watts, a standard measure of electrical energy. For example, a 100 watt
light bulb is brighter because it puts out more energy than a 60 watt bulb.
Think of the effect of waves at the beach: small waves far apart (low strength, low
frequency) versus large wave close together (high strength, high frequency). The exposure to RFR is measured using SAR--specific absorption rate. SAR is
expressed either in milliwatts/kilogram (mW/kg) of body weight or milliwatts/cubic
centimeter (mW/cm2) of exposed body area: the size of the wave and how much of
your body it strikes.
Health Risks
WiFi enthusiasts dismiss health risk concerns because the power output and SAR
exposure is significantly below the minimum standard set for cell phones. But cell
phone standards are set for the short term exposure of a cell phone in use pressed
to your head. Nonthermal effects of cell phones are documented at exposures below the current
US standards, including
- memory loss,
- sleep disruption,
- slowed motor skills and reaction time,
- decreased immune function,
- spatial disorientation and dizziness,
- headaches,
- lowered sperm count,
- increased blood pressure and pulse,
- DNA breakage and reduced DNA repair capacity, and
- cell proliferation.
A second problem is that cell phone exposure is intermittent, whereas WiFi
exposure is constant. A more accurate comparison is to the effect of cell phone
broadcast antennas. These antennas send and receive radio frequency signals
constantly.
The signal strength from an antenna is comparable to a cell phone only at very close
range. The exposure is not a cell phone's brief blast but a persistent bath of low-
strength RFR. In addition to the health effects documented for cell phone use,
exposure to cell phone antennas include
- increased blood pressure and pulse,
- sleep disruption,
- emotional effects such as increased depression and irritability,
- memory loss and mental fog,
- fatique and vertigo, and
- increased cancer risk.
Because of these effects, the International Association of Fire Fighters (AFL-CIO)
decided in 2004 that they will not permit cell phone antennas on fire houses.
RFR Hypersensitivity
Much of the discussion of RFR health effects is framed as a concern with people
who are hypersensitive. Hypersensitivity is the technical term for allergies
and similar immune system overreactions. But instead of pollen, RFR
hypersensitivity is a reaction to nonionizing
radiation. Research by Olle Johansson and Örjan Halberg of the Karolinska Institute, Stockholm
suggests otherwise. They looked at the incidence of cancer in Europe and the US
and found a striking association between the increase in certain cancers during the
20th Century and exposure RFR as measured by radio and TV broadcasts.
What the hypersensitive really represent is one extreme in a complex landscape of
effects and risks. Just like any other environmental stressor, RFR will affect some
people more than others. Wireless LANs add to the existing burden of RFR. Just as burning more fossil fuels
adds more smog, adding more RFR adds more electrosmog. You don't have to
expose your home or your city to the increased burden created by WiFi. There's a
viable alternative: a wired LAN.
You've set up your Boingo account, you're hanging out at the Home Turf sports bar in LAX and you figure you'll do a little business or check your e-mail while sipping a Chardonnay. Don't, however, get so relaxed that you ignore security and give all your confidential information to some unscrupulous hacker. Yep, drinking a Blatz. Sorry, they won't be that obvious, I doubt they ever drink Blatz and very seldom wear clown caps. When you're thinking back, trying to remember who was around when your password was stolen, you probably won't remember the woman in the tastefully tailored business suit, and if, by chance, you do, she won't be the one you suspect. The best defense is to implement some simple security practices and measures that will safeguard your business and personal information. Hot Spot Security: Simple Stuff Be aware of those around you.
When you're considering Wi-Fi security in public places one of the first safeguards is anything but high tech. Remember a few years ago when people were getting huge phone bills because someone was watching as they keyed in pass codes? It's still happening to Wi-Fi network subscribers. You pay good money for your monthly subscription and there's no reason to let anyone piggyback or steal your credit card number as you sign up for a daily use fee at Starbucks. Speaking of passwords:
Use a complex password to protect your files, folders and laptop from access by those villains of concourse and lobby. Don't Share!
Yes, I know, mothers have been telling us to share for centuries but, at least while using a Wi-Fi hotspot, make sure you disable file sharing. Use a Personal Firewall.
If you're using a corporate laptop make sure you talk to your IT department before you install any firewalls but if the laptop you're using is your own let me suggest downloading a copy of ZoneAlarm. Hot Spot Security: Less Simple Stuff Beware the Evil Twin
Otherwise known as 'Rogue Hotspots' or the 'soft AP attack' this Wi-Fi version of the e-mail Phishing scam is perpetrated by hackers who jam and mimic the signal and SSID of a legitimate hotspot. They then serve up a sign-in page garnering usernames, passwords and, in some cases, credit card numbers. If they go so far as to allow a connection to the Internet they're then in the position to intercept unencrypted traffic as well as any files open to sharing (Don't Share!).
Don't set your Wi-Fi card to allow automatic connection to any available network.
Turn off the ad-hoc mode allowing other clients to connect directly to you.
Turn off your Wi-Fi card entirely as soon as you're finished.
Use the personal or enterprise version of 'AirDefense', whichever may be appropriate.
Although a firewall won't keep you from connecting to an 'Evil Twin' it will help to safeguard your information should you inadvertently fall victim.
Encrypt Confidential Information
Data that's transmitted between yourself and a secure Web site can be counted on to be safe from the Starbucks Snidely Whiplash so when you're purchasing goods, or banking on-line, you can do so without fear. When you're logging onto the secure portion of the site, however, you may be doing so without the protection of security so be careful to note whether or not the sign in page is secured (https).
For example, instead of using Outlook or Thunderbird, take advantage of your ISP's Web interface which, in most cases, will be secure and should protect your data during transmission.
If you frequently encounter the need to send large files via e-mail then using a compression program will meet your need to reduce the size of the file and most compression programs will also secure the data with encryption.
Another option is to use a free encryption program like Cryptainer LE. Cryptainer LE can encrypt any or all the files stored on your hard drive, protecting them in case your laptop is stolen or compromised, as well as allow you to e-mail them with the security of encryption. Cryptainer PE is also offered for enterprise applications.
Use a Virtual Private Network
Think of a virtual private network (VPN) as a solid conduit, or tunnel, between your laptop and your company's network. Mac OS X(TM), Windows(TM) 2000 and Windows(TM) XP have built in VPN clients and if you're a user of Windows(TM) 98, ME or NT you can download the free Microsoft® L2TP/IPSec VPN Client from Microsoft®. If you're a Linux user you can download the free S/WAN VPN client.
While the use of a VPN is one of the best ways to protect your confidential data when you're using a Wi-Fi hotspot it is, unfortunately, limited to communication between your laptop and your company's server. If you want to conduct personal business with similar security levels the best solution may be the award winning GoToMyPC software.
Use Anti-Virus Software
It's somewhat surprising that so many people are aware of the dangers of 'net borne viruses and, yet, so many either fail to incorporate anti-virus programs like McAfee & Norton or fail to keep them up to date. When you're using a public hotspot it's more important than ever to have anti virus software installed.
Once you've got the software up and running make sure that it's updated on a regular basis and update it anytime you hear about a new virus or a new version of an old virus. If you've got an auto-update feature built into your program make sure you take advantage of it.
Conclusion
By following these security measure you should be able to enjoy,with the confidence that your private information will remain private,your favorite Wi-Fi hotspots around the world
