A device that detects the presence of an 802.11 network. Also called a "Wi-Fi finder" or "Wi-Fi signal finder," it lets you know if a wifi spot or spots are available without having to turn on your laptop. Handheld finders may have readouts that identify the network ID and status, while keychain-based units blink LEDs to show signal strength.
The Handheld wifi spots finder
The Digital wifi spots finder from Canary Wireless does more than just indicate the signal strenghts of free Wi-Fi spots within rangeb, its readout describes the networks it finds, including the network's name ID (SSID), signal strength, encryption status (Open or Secure) and channel number.
The readout will currently display the SSID of the best free wifi signal network it finds and all other networks available.
Tuesday, August 11, 2009
Wi-Fi Hardware standard devices
Wireless Access Point(AP)
Wireless access points connect a group of wireless devices to an adjacent wired LAN. An access point is similar to an Ethernet hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an Ethernet hub or switch, permitting wireless devices to communicate with other wired devices. An AP can be used ton create a free wifi spot and if it is configured without any security, the network becomes vulnerable to attacks so much that wifi dummies can easily access the internet through it.
Wireless Adapter
Wireless adapters allow computer devices to connect to a wifi (wireless) network. These adapters connect to these devices using various external or internal interconnects such as PCI, miniPCI, USB, ExpressCard, Cardbus and PC card. Most newer laptop computers are equipped with internal adapters. Internal cards are generally more difficult to install.
Wireless routers integrate a WAP, Ethernet switch, and internal Router firmware application that provides IP Routing, NAT, and DNS forwarding through an integrated WAN interface. A wireless router allows wired and wireless ethernet LAN devices to connect to a (usually) single WAN device such as cable modem or DSL modem. A wireless router allows all these devices (mainly the access point and router) to be configured through one central utility. A router can be configured in such a way that it becomes a free wifi broadcasting spot if done without security in mind.
This utility is most usually an integrated web server which serves web pages to wired and wireless LAN clients and often optionally to WAN clients. This utility may also be an application that is run on a desktop computer such as Apple's AirPort.
Wireless Ethernet bridges connect a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the . Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.
Wireless range extenders or wireless repeaters can extend the range of an existing wireless network. Range extenders can be strategically placed to elongate a signal area or allow for the signal area to reach around barriers such as those created in L-shaped corridors. Wireless devices connected through repeaters will suffer from an increased latency for each hop. Additionally, a wireless device connected to any of the repeaters in the chain throughput that is limited by the weakest link between the two nodes in the chain from which the connection originates to where the connection ends.
Most commercial devices (routers, access points, bridges, repeaters) designed for home or business environments use either RP-SMA or RP-TNC antenna connectors. PCI wireless adapters also mainly use RP-SMA connectors. Most PC card and USB wireless only have internal antennas etched on their printed circuit board while some have MMCX connector or MC-Card external connections in addition to an internal antenna. A few USB cards have a RP-SMA connector.
Most Mini PCI wireless cards use Hirose U.FL connectors, but cards found in various wireless appliances contain all of the connectors listed. Many high-gain (and home made antennas) use the Type N connector more commonly used by other radio communications methods.
Non-standard devices
The longest link ever achieved was by the Swedish space agency. They attained 310 km, but used 6 watt amplifiers to reach an overhead stratospheric balloon. The longest link without amplification was 279 km in Venezuela, 2006
Wireless access points connect a group of wireless devices to an adjacent wired LAN. An access point is similar to an Ethernet hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an Ethernet hub or switch, permitting wireless devices to communicate with other wired devices. An AP can be used ton create a free wifi spot and if it is configured without any security, the network becomes vulnerable to attacks so much that wifi dummies can easily access the internet through it.
Wireless Adapter
Wireless adapters allow computer devices to connect to a wifi (wireless) network. These adapters connect to these devices using various external or internal interconnects such as PCI, miniPCI, USB, ExpressCard, Cardbus and PC card. Most newer laptop computers are equipped with internal adapters. Internal cards are generally more difficult to install.
Wireless routers integrate a WAP, Ethernet switch, and internal Router firmware application that provides IP Routing, NAT, and DNS forwarding through an integrated WAN interface. A wireless router allows wired and wireless ethernet LAN devices to connect to a (usually) single WAN device such as cable modem or DSL modem. A wireless router allows all these devices (mainly the access point and router) to be configured through one central utility. A router can be configured in such a way that it becomes a free wifi broadcasting spot if done without security in mind.
This utility is most usually an integrated web server which serves web pages to wired and wireless LAN clients and often optionally to WAN clients. This utility may also be an application that is run on a desktop computer such as Apple's AirPort.
Wireless Ethernet bridges connect a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the . Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.
Wireless range extenders or wireless repeaters can extend the range of an existing wireless network. Range extenders can be strategically placed to elongate a signal area or allow for the signal area to reach around barriers such as those created in L-shaped corridors. Wireless devices connected through repeaters will suffer from an increased latency for each hop. Additionally, a wireless device connected to any of the repeaters in the chain throughput that is limited by the weakest link between the two nodes in the chain from which the connection originates to where the connection ends.
Most commercial devices (routers, access points, bridges, repeaters) designed for home or business environments use either RP-SMA or RP-TNC antenna connectors. PCI wireless adapters also mainly use RP-SMA connectors. Most PC card and USB wireless only have internal antennas etched on their printed circuit board while some have MMCX connector or MC-Card external connections in addition to an internal antenna. A few USB cards have a RP-SMA connector.
Most Mini PCI wireless cards use Hirose U.FL connectors, but cards found in various wireless appliances contain all of the connectors listed. Many high-gain (and home made antennas) use the Type N connector more commonly used by other radio communications methods.
Non-standard devices
The longest link ever achieved was by the Swedish space agency. They attained 310 km, but used 6 watt amplifiers to reach an overhead stratospheric balloon. The longest link without amplification was 279 km in Venezuela, 2006
Free Wi-Fi spots can become a Pollution
Uncontrolled Wi-Fi hotspots can become a pollution, whenever there is an excessive deployment of a number of access points in an area, especially on the same or around a neighborhood channel, can prevent access and interfere with the use of other access points by others, caused by overlapping channels in the 802.11g/b spectrum, as well as with decreased signal-to-noise ratio (SNR) between access points.
This can be a problem in high-density areas, such as large apartment complexes or office buildings with many Wi-Fi access points.
Additionally, other devices using the 2.4 GHz band: microwave ovens, security cameras, Bluetooth devices and (in some countries) Amateur radio, video-senders, cordless phones and baby monitors can cause significant additional interference.
General a guide to those who suffer from these forms of interference or network crowding is to migrate to a WiFi 5 GHz product (802.11a) usually a dual band product as the 5 GHz band is
relatively unused and there are many more channels available. This also requires users to set up the 5 GHz band to be the preferred network in the client and to configure each network band to a different name(SSID).
Excessive free Wifi spots becomes an issue when municipalities or other large entities such as universities, seek to provide large area coverage. Everyone is considered equal for the base standard without 802.11e/WMM when they use the band.
This openness is also important to the success and widespread use of 2.4 GHz Wi-Fi, but makes it unsuitable for "must-have" public service functions or where reliability is required.
Interoperability issues between brands or proprietary deviations from the standard can disrupt connections or lower throughput speeds on other user's devices that are within range. For anyone one seeking to set up a wifi spots must ensure the environment is filled with heavy interferences of broadcasting network which becomes an problem if we really want to liberate our novice friend from the "wifi for dummies domain"
This can be a problem in high-density areas, such as large apartment complexes or office buildings with many Wi-Fi access points.
Additionally, other devices using the 2.4 GHz band: microwave ovens, security cameras, Bluetooth devices and (in some countries) Amateur radio, video-senders, cordless phones and baby monitors can cause significant additional interference.
General a guide to those who suffer from these forms of interference or network crowding is to migrate to a WiFi 5 GHz product (802.11a) usually a dual band product as the 5 GHz band is
relatively unused and there are many more channels available. This also requires users to set up the 5 GHz band to be the preferred network in the client and to configure each network band to a different name(SSID).
Excessive free Wifi spots becomes an issue when municipalities or other large entities such as universities, seek to provide large area coverage. Everyone is considered equal for the base standard without 802.11e/WMM when they use the band.
This openness is also important to the success and widespread use of 2.4 GHz Wi-Fi, but makes it unsuitable for "must-have" public service functions or where reliability is required.
Interoperability issues between brands or proprietary deviations from the standard can disrupt connections or lower throughput speeds on other user's devices that are within range. For anyone one seeking to set up a wifi spots must ensure the environment is filled with heavy interferences of broadcasting network which becomes an problem if we really want to liberate our novice friend from the "wifi for dummies domain"
Draw-backs to free WI-Fi technology
One of the most crucial advantage that wireless network has over wired counterpart is that Wi-Fi allows LANs to be deployed without cabling for client devices, typically reducing the costs of network deployment and expansion. Spaces where cables cannot be run, such as outdoor areas and historical buildings, can host wireless LANs or set up a wifi spot.
As of 2007 wireless network adapters are built already into most modern laptops. The price of chipsets for Wi-Fi continues to drop, making it an economical networking option included in ever more devices. Wi-Fi has become widespread in corporate infrastructures, which also helps with the deployment of RFID technology that can piggyback on Wi-Fi account.
Different competitive brands of access points and client network interfaces are inter-operable at a basic level of service to make it ever so easy for wifi dummies to to connect utilize with little or no tech assistance . Products designated as "Wi-Fi Certified" by the Wi-Fi Alliance are backwards inter-operable.
Wi-Fi is a global set of standards. Unlike mobile telephones, any standard Wi-Fi device will work anywhere in the world. Wi-Fi is widely available in more than 250,000 public hotspots and tens of millions of homes, corporate settings and university campuses worldwide. WPA is not easily cracked if strong passwords are used and WPA2 encryption has no known weaknesses. New protocols for Quality of Service (WMM) make Wi-Fi more suitable for latency-sensitive applications (such as voice and video), and power saving mechanisms (WMM Power Save) improve battery operation.
Disadvantages of Wi-Fi
It is difficult to find any technology without limitations. This article is pertinent that all wifi users must take note of especially for anyone that is still nursing the thought that it is meant for wifi dummies. Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for an additional 2 channels beyond those permitted in the U.S for the 2.4 GHz band. (1-13 vs. 1-11); Japan has one more on top of that (1-14). Europe, as of 2007, is now essentially homogeneous in this respect.
A very confusing aspect is the fact a WiFI signal actually occupies five channels in the 2.4 GHz resulting in only 3 non-overlapped channels in the US: 1, 6, 11, and four in Europe: 1,5,9,13
Some countries, such as Italy, formerly required a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration. Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm (0.1 W).
Power consumption is fairly high compared to some other low-bandwidth standards, such as Zigbee and Bluetooth, making battery life a concern. The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an open (encryption-free) mode.
Novice users benefit from a zero-configuration device that works out of the box, but this default is without security enabled, providing open wireless access to their LAN. These configuration should not be seen as a lee way to bypass all the so called problem of connecting to wifi usually experienced by new users. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI).
Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. ("Wifi for Dummies: HTTPS/Secure Socket Layer.) Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain wireless channels.
To change the channel of operation for an access point requires the user to configure the device.
Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or 802.11g with a stock antenna might have a range of 32 m (120 ft) indoors and 95 m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor range with improved (directional) antennas can be several kilometers(kilometres) or more with line-of-sight.
Wi-Fi performance also decreases exponentially as the range increases. Wi-Fi is also less reliable and fast as Ethernet or other cable systems, 802.11g networks have a maximum of 54 Mbit/s whilst cables can reach speeds of 1000 Mbit/s or more. wifi is not suitable for servers or users who need fast internet access, for example, online gamers.
As of 2007 wireless network adapters are built already into most modern laptops. The price of chipsets for Wi-Fi continues to drop, making it an economical networking option included in ever more devices. Wi-Fi has become widespread in corporate infrastructures, which also helps with the deployment of RFID technology that can piggyback on Wi-Fi account.
Different competitive brands of access points and client network interfaces are inter-operable at a basic level of service to make it ever so easy for wifi dummies to to connect utilize with little or no tech assistance . Products designated as "Wi-Fi Certified" by the Wi-Fi Alliance are backwards inter-operable.
Wi-Fi is a global set of standards. Unlike mobile telephones, any standard Wi-Fi device will work anywhere in the world. Wi-Fi is widely available in more than 250,000 public hotspots and tens of millions of homes, corporate settings and university campuses worldwide. WPA is not easily cracked if strong passwords are used and WPA2 encryption has no known weaknesses. New protocols for Quality of Service (WMM) make Wi-Fi more suitable for latency-sensitive applications (such as voice and video), and power saving mechanisms (WMM Power Save) improve battery operation.
Disadvantages of Wi-Fi
It is difficult to find any technology without limitations. This article is pertinent that all wifi users must take note of especially for anyone that is still nursing the thought that it is meant for wifi dummies. Spectrum assignments and operational limitations are not consistent worldwide. Most of Europe allows for an additional 2 channels beyond those permitted in the U.S for the 2.4 GHz band. (1-13 vs. 1-11); Japan has one more on top of that (1-14). Europe, as of 2007, is now essentially homogeneous in this respect.
A very confusing aspect is the fact a WiFI signal actually occupies five channels in the 2.4 GHz resulting in only 3 non-overlapped channels in the US: 1, 6, 11, and four in Europe: 1,5,9,13
Some countries, such as Italy, formerly required a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration. Equivalent isotropically radiated power (EIRP) in the EU is limited to 20 dBm (0.1 W).
Power consumption is fairly high compared to some other low-bandwidth standards, such as Zigbee and Bluetooth, making battery life a concern. The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an open (encryption-free) mode.
Novice users benefit from a zero-configuration device that works out of the box, but this default is without security enabled, providing open wireless access to their LAN. These configuration should not be seen as a lee way to bypass all the so called problem of connecting to wifi usually experienced by new users. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI).
Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. ("Wifi for Dummies: HTTPS/Secure Socket Layer.) Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain wireless channels.
To change the channel of operation for an access point requires the user to configure the device.
Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or 802.11g with a stock antenna might have a range of 32 m (120 ft) indoors and 95 m (300 ft) outdoors. Range also varies with frequency band. Wi-Fi in the 2.4 GHz frequency block has slightly better range than Wi-Fi in the 5 GHz frequency block. Outdoor range with improved (directional) antennas can be several kilometers(kilometres) or more with line-of-sight.
Wi-Fi performance also decreases exponentially as the range increases. Wi-Fi is also less reliable and fast as Ethernet or other cable systems, 802.11g networks have a maximum of 54 Mbit/s whilst cables can reach speeds of 1000 Mbit/s or more. wifi is not suitable for servers or users who need fast internet access, for example, online gamers.
Wifi for Dummies: Wi-Fi Security concern of a Public network
Unsecured free wifi spots:
Most wifi spots are unsecured. User data is shared as clear text as all users access the internet via free wifi spots. Though some hotspots authenticate users. This does not secure the data transmission or prevent packet sniffers from allowing people to see traffic on the network.
Some free wifi venues offer VPN as an option, such as Google WiFi. This solution is expensive to scale. Others such as T-mobile provide a download option that deploys WPA support specific to T-mobile. This conflicts with enterprise configurations at Cisco, IBM, HP, Google, and other large enterprises who have solutions specific to their internal WLAN.
"Poisoned free wifi spots:"
A "poisoned spot" refers to a free public hotspot set up by identity thieves or other malicious individuals for the purpose of "sniffing" the data sent by the user. This abuse can be avoided by the use of VPN.
Wi-Fi Protected Access - (WPA)
A Wi-Fi Protected Access security scheme for wireless networks, developed by the networking industry in response to the shortcomings of Wired Equivalent Privacy (WEP). WPA uses Temporal Key Integrity Protocol (TKIP) encryption and provides built-in authentication, giving security comparable to VPN tunneling with WEP, with the benefit of easier administration and use. WPA-PSK is a simplified form of WPA.
Wifi phone:
A WiFi phone is a wireless telephone that looks similar to a mobile phone but places calls via a combination of voice over IP and WiFi rather than via a cellular network. Current WiFi phones use Skype or Vonage for their voice over IP service. To compete with WiFi phones, several cellular carriers have created "Dual-mode phones", which can be easily switched between using a WiFi connection when one is available and a traditional cellular network connection when WiFi is not available. These phone can easily be connected to to free wifi network by following set up instructions.
Wi-Fi Protected Access (WPA and WPA2):
A Wi-Fi Protected Access is a class of systems to secure wireless (Wi-Fi) computer networks. It was created in response to several serious weaknesses researchers had found in the previous system, Wired Equivalent Privacy (WEP). WPA implements the majority of the IEEE 802.11i standard, and was intended as an intermediate measure to take the place of WEP while 802.11i was prepared. WPA is designed to work with all wireless network interface cards, but not necessarily with first generation wireless access points.
WPA2:
WPA2 implements the full standard, but will not work with some older network cards. Both provide good security, with two significant issues:
• Either WPA or WPA2 must be enabled and chosen in preference to WEP. WEP is usually presented as the first security choice in most installation instructions.
• In the "Personal" mode, the most likely choice for homes and small offices, a passphrase is required that, for full security, must be longer than the typical 6 to 8 character passwords users often employ.
History:
WPA was created by the Wi-Fi Alliance, an industry trade group, which owns the trademark to the Wi-Fi name and certifies devices that carry that name.
WPA is designed for use with an IEEE 802.1X authentication server, which distributes different keys to each user; however, it can also be used in a less secure "pre-shared key" (PSK) mode, where every user is given the same pass-phrase. The design of WPA is based on a Draft 3 of the IEEE 802.11i standard.
The Wi-Fi Alliance created WPA to enable introduction of standard-based secure wireless network products prior to the IEEE 802.11i group finishing its work. The Wi-Fi Alliance at the time had already anticipated the WPA2 certification based on the final draft of the IEEE 802.11i standard. Therefore, they intentionally made the tags on the frame fields (also known as information elements, or IEs) made different from 802.11i to avoid the confusion in unified WPA/WPA2 implementations.
Data is encrypted using the RC4 stream cipher, with a 128-bit key and a 48-bit initialization vector (IV). One major improvement in WPA over WEP is the Temporal Key Integrity Protocol (TKIP), which dynamically changes keys as the system is used. When combined with the much larger initialization vector, this defeats the well-known key recovery attacks on WEP.
In addition to authentication and encryption, WPA also provides vastly improved payload integrity. The cyclic redundancy check (CRC) used in WEP is inherently insecure; it is possible to alter the payload and update the message CRC without knowing the WEP key. A more secure message authentication code (usually known as a MAC, but here termed a MIC for "message integrity code") is used in WPA, an algorithm named "Michael".
The MIC used in WPA includes a frame counter, which prevents replay attacks being executed.
By increasing the size of the keys and IVs, reducing the number of packets sent with related keys, and adding a secure message verification system, WPA makes breaking into a wireless LAN far more difficult. The Michael algorithm was the strongest that WPA designers could come up with that would still work with most older network cards.
Due to inevitable weaknesses of Michael, TKIP will shut down the network for one minute if two frames are discovered that fail the Michael check after passing all other integrity checks that would have caught noisy frames. It will then require generation of new keys and reauthentication when the network restarts, forcing the attacker to start over.
Most wifi spots are unsecured. User data is shared as clear text as all users access the internet via free wifi spots. Though some hotspots authenticate users. This does not secure the data transmission or prevent packet sniffers from allowing people to see traffic on the network.
Some free wifi venues offer VPN as an option, such as Google WiFi. This solution is expensive to scale. Others such as T-mobile provide a download option that deploys WPA support specific to T-mobile. This conflicts with enterprise configurations at Cisco, IBM, HP, Google, and other large enterprises who have solutions specific to their internal WLAN.
"Poisoned free wifi spots:"
A "poisoned spot" refers to a free public hotspot set up by identity thieves or other malicious individuals for the purpose of "sniffing" the data sent by the user. This abuse can be avoided by the use of VPN.
Wi-Fi Protected Access - (WPA)
A Wi-Fi Protected Access security scheme for wireless networks, developed by the networking industry in response to the shortcomings of Wired Equivalent Privacy (WEP). WPA uses Temporal Key Integrity Protocol (TKIP) encryption and provides built-in authentication, giving security comparable to VPN tunneling with WEP, with the benefit of easier administration and use. WPA-PSK is a simplified form of WPA.
Wifi phone:
A WiFi phone is a wireless telephone that looks similar to a mobile phone but places calls via a combination of voice over IP and WiFi rather than via a cellular network. Current WiFi phones use Skype or Vonage for their voice over IP service. To compete with WiFi phones, several cellular carriers have created "Dual-mode phones", which can be easily switched between using a WiFi connection when one is available and a traditional cellular network connection when WiFi is not available. These phone can easily be connected to to free wifi network by following set up instructions.
Wi-Fi Protected Access (WPA and WPA2):
A Wi-Fi Protected Access is a class of systems to secure wireless (Wi-Fi) computer networks. It was created in response to several serious weaknesses researchers had found in the previous system, Wired Equivalent Privacy (WEP). WPA implements the majority of the IEEE 802.11i standard, and was intended as an intermediate measure to take the place of WEP while 802.11i was prepared. WPA is designed to work with all wireless network interface cards, but not necessarily with first generation wireless access points.
WPA2:
WPA2 implements the full standard, but will not work with some older network cards. Both provide good security, with two significant issues:
• Either WPA or WPA2 must be enabled and chosen in preference to WEP. WEP is usually presented as the first security choice in most installation instructions.
• In the "Personal" mode, the most likely choice for homes and small offices, a passphrase is required that, for full security, must be longer than the typical 6 to 8 character passwords users often employ.
History:
WPA was created by the Wi-Fi Alliance, an industry trade group, which owns the trademark to the Wi-Fi name and certifies devices that carry that name.
WPA is designed for use with an IEEE 802.1X authentication server, which distributes different keys to each user; however, it can also be used in a less secure "pre-shared key" (PSK) mode, where every user is given the same pass-phrase. The design of WPA is based on a Draft 3 of the IEEE 802.11i standard.
The Wi-Fi Alliance created WPA to enable introduction of standard-based secure wireless network products prior to the IEEE 802.11i group finishing its work. The Wi-Fi Alliance at the time had already anticipated the WPA2 certification based on the final draft of the IEEE 802.11i standard. Therefore, they intentionally made the tags on the frame fields (also known as information elements, or IEs) made different from 802.11i to avoid the confusion in unified WPA/WPA2 implementations.
Data is encrypted using the RC4 stream cipher, with a 128-bit key and a 48-bit initialization vector (IV). One major improvement in WPA over WEP is the Temporal Key Integrity Protocol (TKIP), which dynamically changes keys as the system is used. When combined with the much larger initialization vector, this defeats the well-known key recovery attacks on WEP.
In addition to authentication and encryption, WPA also provides vastly improved payload integrity. The cyclic redundancy check (CRC) used in WEP is inherently insecure; it is possible to alter the payload and update the message CRC without knowing the WEP key. A more secure message authentication code (usually known as a MAC, but here termed a MIC for "message integrity code") is used in WPA, an algorithm named "Michael".
The MIC used in WPA includes a frame counter, which prevents replay attacks being executed.
By increasing the size of the keys and IVs, reducing the number of packets sent with related keys, and adding a secure message verification system, WPA makes breaking into a wireless LAN far more difficult. The Michael algorithm was the strongest that WPA designers could come up with that would still work with most older network cards.
Due to inevitable weaknesses of Michael, TKIP will shut down the network for one minute if two frames are discovered that fail the Michael check after passing all other integrity checks that would have caught noisy frames. It will then require generation of new keys and reauthentication when the network restarts, forcing the attacker to start over.
Free Wi-Fi hotspots For The general public
Free hotspots Wi-Wi operates in two ways:
• Using an open public network is the easiest way to create a free HotSpot. All that is needed is a Wi-Fi router. However, the disadvantage is that access to the router cannot be controlled.
• Closed public networks use a HotSpot Management System to control the HotSpot. This software runs on the router itself or uses an external computer for it. With the help of this software, operators can authorize only specific users to be able to access the internet, and they often associate the free access to a menu or to a purchase limit.
• Using an open public network is the easiest way to create a free HotSpot. All that is needed is a Wi-Fi router. However, the disadvantage is that access to the router cannot be controlled.
• Closed public networks use a HotSpot Management System to control the HotSpot. This software runs on the router itself or uses an external computer for it. With the help of this software, operators can authorize only specific users to be able to access the internet, and they often associate the free access to a menu or to a purchase limit.
Commercial hotspots (For WIFI Technology)
A commercial hotspot may feature:
• A captive portal that users are redirected to for authentication and payment
• A payment option using credit card, PayPal, BOZII, iPass, or other payment service
• A walled garden feature that allows free access to certain sites
Many services provide payment services to hotspot providers, for a monthly fee or commission from the end-user income. ZoneCD is a Linux distribution that provides payment services for hotspots who wish to deploy their own service.
Major airports and business hotels are more likely to charge for service. Most hotels provide free service to guests; and increasingly small airports and airline lounges offer free service.
FON is a European company that allows users to share their wireless broadband and sells excess bandwidth to outside users (Aliens). Since this may breach users terms of service FON has agreements with many broadband providers / ISPs.
The nature of commercial WiFi has seen a profound shift since its first adoption. Much like O’Reilly’s term “Web 2.0” has come to represent the current and next generation of web sites and web applications like Wikipedia, Craig’s List, blogging, and Google’s personalized homepage, Joshua Beil coined the term "WiFi 2.0" to represent the evolution of commercial WiFi.
Whereas WiFi 1.0 was characterized by:
• Single location, short range
• Non revenue generating or manual methods of revenue collection
• Unsecure or WEP
• No branding
• No localized content/advertising
• No gathering of user demographic data
WiFi 2.0 is characterized by:
• Multiple locations and/or mesh splash page portals
• User revenues and or sponsor-based revenues generated
• Partial or fully branded by location or provider
• Location-based content and advertising
• Survey and other tools to gather intelligence about users
• A captive portal that users are redirected to for authentication and payment
• A payment option using credit card, PayPal, BOZII, iPass, or other payment service
• A walled garden feature that allows free access to certain sites
Many services provide payment services to hotspot providers, for a monthly fee or commission from the end-user income. ZoneCD is a Linux distribution that provides payment services for hotspots who wish to deploy their own service.
Major airports and business hotels are more likely to charge for service. Most hotels provide free service to guests; and increasingly small airports and airline lounges offer free service.
FON is a European company that allows users to share their wireless broadband and sells excess bandwidth to outside users (Aliens). Since this may breach users terms of service FON has agreements with many broadband providers / ISPs.
The nature of commercial WiFi has seen a profound shift since its first adoption. Much like O’Reilly’s term “Web 2.0” has come to represent the current and next generation of web sites and web applications like Wikipedia, Craig’s List, blogging, and Google’s personalized homepage, Joshua Beil coined the term "WiFi 2.0" to represent the evolution of commercial WiFi.
Whereas WiFi 1.0 was characterized by:
• Single location, short range
• Non revenue generating or manual methods of revenue collection
• Unsecure or WEP
• No branding
• No localized content/advertising
• No gathering of user demographic data
WiFi 2.0 is characterized by:
• Multiple locations and/or mesh splash page portals
• User revenues and or sponsor-based revenues generated
• Partial or fully branded by location or provider
• Location-based content and advertising
• Survey and other tools to gather intelligence about users
History of wi-fi (Wireless network)
Wi-Fi hotspots were first proposed by Brett Stewart at the NetWorld+Interop conference in The Moscone Center in San
Francisco in August 1993. Stewart did not use the term 'hotspot' but referred to public accessible wireless LANs.
Stewart went on to found the companies PLANCOM in 1994 (for Public LAN Communications, which became MobileStar and
then the hotspot arm of T-Mobile) and subsequently Wayport in 1996.
The term 'HotSpot' may have first been advanced by Nokia about five years after Stewart first proposed the concept.
During the dot-com boom and subsequent bust in 2000, dozens of companies like WPMedia of the Rural Agriculture town
of Kingstree SC had the notion that Wi-Fi could become the payphone for broadband.
Although WPMedia Inc. invented, developed and patented United States Patent 7,035,281, <[1] (retrieved on 2007-09-
20) the concept of authenication, metering and billing for public domain WiFi use, the company's implementation
never expanded beyond a few hundred square miles. The original notion was that users would pay for broadband access
at hotspots and then expand to a completely roaming network. Although some companies like T-mobile, and Boingo have
had some success with charging for access, over 90% of the over 300,000 hotspots offer free service to entice
customers to their venue.
Free hotspots continue to grow. Wireless networks that cover entire cities, such as municipal broadband have
mushroomed. MuniWireless reports that over 300 metropolitan projects have been started.
Many business models have emerged for hotspots. The final structure of the hotspot marketplace will ultimately have
to consider the intellectual property rights of the early movers; portfolios of more than 1000 allowed and pending
patent claims are held by some of these parties.
Commercial hotspots
A commercial hotspot may feature:
• A captive portal that users are redirected to for authentication and payment
• A payment option using credit card, PayPal, BOZII, iPass, or other payment service
• A walled garden feature that allows free access to certain sites
Many services provide payment services to hotspot providers, for a monthly fee or commission from the end-user
income. ZoneCD is a Linux distribution that provides payment services for hotspots who wish to deploy their own
service.
Major airports and business hotels are more likely to charge for service. Most hotels provide free service to
guests; and increasingly small airports and airline lounges offer free service.
FON is a European company that allows users to share their wireless broadband and sells excess bandwidth to outside
users (Aliens). Since this may breach users terms of service FON has agreements with many broadband providers /
ISPs.
The nature of commercial WiFi has seen a profound shift since its first adoption. Much like O’Reilly’s term “Web
2.0” has come to represent the current and next generation of web sites and web applications like Wikipedia,
Craig’s List, blogging, and Google’s personalized homepage, Joshua Beil coined the term "WiFi 2.0" to represent the
evolution of commercial WiFi.
Whereas WiFi 1.0 was characterized by:
• Single location, short range
• Non revenue generating or manual methods of revenue collection
• Unsecure or WEP
• No branding
• No localized content/advertising
• No gathering of user demographic data
WiFi 2.0 is characterized by:
• Multiple locations and/or mesh splash page portals
• User revenues and or sponsor-based revenues generated
• Partial or fully branded by location or provider
• Location-based content and advertising
• Survey and other tools to gather intelligence about users
Francisco in August 1993. Stewart did not use the term 'hotspot' but referred to public accessible wireless LANs.
Stewart went on to found the companies PLANCOM in 1994 (for Public LAN Communications, which became MobileStar and
then the hotspot arm of T-Mobile) and subsequently Wayport in 1996.
The term 'HotSpot' may have first been advanced by Nokia about five years after Stewart first proposed the concept.
During the dot-com boom and subsequent bust in 2000, dozens of companies like WPMedia of the Rural Agriculture town
of Kingstree SC had the notion that Wi-Fi could become the payphone for broadband.
Although WPMedia Inc. invented, developed and patented United States Patent 7,035,281, <[1] (retrieved on 2007-09-
20) the concept of authenication, metering and billing for public domain WiFi use, the company's implementation
never expanded beyond a few hundred square miles. The original notion was that users would pay for broadband access
at hotspots and then expand to a completely roaming network. Although some companies like T-mobile, and Boingo have
had some success with charging for access, over 90% of the over 300,000 hotspots offer free service to entice
customers to their venue.
Free hotspots continue to grow. Wireless networks that cover entire cities, such as municipal broadband have
mushroomed. MuniWireless reports that over 300 metropolitan projects have been started.
Many business models have emerged for hotspots. The final structure of the hotspot marketplace will ultimately have
to consider the intellectual property rights of the early movers; portfolios of more than 1000 allowed and pending
patent claims are held by some of these parties.
Commercial hotspots
A commercial hotspot may feature:
• A captive portal that users are redirected to for authentication and payment
• A payment option using credit card, PayPal, BOZII, iPass, or other payment service
• A walled garden feature that allows free access to certain sites
Many services provide payment services to hotspot providers, for a monthly fee or commission from the end-user
income. ZoneCD is a Linux distribution that provides payment services for hotspots who wish to deploy their own
service.
Major airports and business hotels are more likely to charge for service. Most hotels provide free service to
guests; and increasingly small airports and airline lounges offer free service.
FON is a European company that allows users to share their wireless broadband and sells excess bandwidth to outside
users (Aliens). Since this may breach users terms of service FON has agreements with many broadband providers /
ISPs.
The nature of commercial WiFi has seen a profound shift since its first adoption. Much like O’Reilly’s term “Web
2.0” has come to represent the current and next generation of web sites and web applications like Wikipedia,
Craig’s List, blogging, and Google’s personalized homepage, Joshua Beil coined the term "WiFi 2.0" to represent the
evolution of commercial WiFi.
Whereas WiFi 1.0 was characterized by:
• Single location, short range
• Non revenue generating or manual methods of revenue collection
• Unsecure or WEP
• No branding
• No localized content/advertising
• No gathering of user demographic data
WiFi 2.0 is characterized by:
• Multiple locations and/or mesh splash page portals
• User revenues and or sponsor-based revenues generated
• Partial or fully branded by location or provider
• Location-based content and advertising
• Survey and other tools to gather intelligence about users
What is it about WI-FI
Wi-Fi Logo
A logo from the Wi-Fi Alliance that certifies network devices comply with the IEEE 802.11 wireless Ethernet standards. In the early 2000s, Wi-Fi/802.11 became widely used (initially 802.11b, then 802.11g), and within a short time, all laptops and other handheld devices came with Wi-Fi built in. Earlier laptops can be Wi-Fi enabled by plugging in a Wi-Fi adapter via the USB port or PC Card. For details about how Wi-Fi fits into a home or office network, see wireless LAN.
What's in a Name?
Wi-Fi sounds a lot like "hi-fi," thus it is mistaken to stand for "wireless fidelity." Although the term may have been inspired by "high-fidelity," Wi-Fi is officially just a catchy name, not "wireless fidelity."
A hotspot is a venue that offers Wi-Fi access. The public can use a laptop, Wi-Fi phone, or other suitable portable device to access the Internet. Of the estimated 150 million laptops, 14 million PDAs, and other emerging Wi-Fi devices sold per year for the last few years, most include the Wi-Fi feature.
For venues that have broadband service, offering wireless access is as simple as purchasing one AP and connecting the AP with the gateway box.
Hotspots are often found at restaurants, train stations, airports, libraries, coffee shops, bookstores, fuel stations, department stores, supermarkets and other public places. Many universities and schools have wireless networks in their campus.
A logo from the Wi-Fi Alliance that certifies network devices comply with the IEEE 802.11 wireless Ethernet standards. In the early 2000s, Wi-Fi/802.11 became widely used (initially 802.11b, then 802.11g), and within a short time, all laptops and other handheld devices came with Wi-Fi built in. Earlier laptops can be Wi-Fi enabled by plugging in a Wi-Fi adapter via the USB port or PC Card. For details about how Wi-Fi fits into a home or office network, see wireless LAN.
What's in a Name?
Wi-Fi sounds a lot like "hi-fi," thus it is mistaken to stand for "wireless fidelity." Although the term may have been inspired by "high-fidelity," Wi-Fi is officially just a catchy name, not "wireless fidelity."
A hotspot is a venue that offers Wi-Fi access. The public can use a laptop, Wi-Fi phone, or other suitable portable device to access the Internet. Of the estimated 150 million laptops, 14 million PDAs, and other emerging Wi-Fi devices sold per year for the last few years, most include the Wi-Fi feature.
For venues that have broadband service, offering wireless access is as simple as purchasing one AP and connecting the AP with the gateway box.
Hotspots are often found at restaurants, train stations, airports, libraries, coffee shops, bookstores, fuel stations, department stores, supermarkets and other public places. Many universities and schools have wireless networks in their campus.
A Wirless Network Bridge (WI-FI Technology for dummies)
A wireless bridge can be used to connect networks, typically of different types. A wireless Ethernet bridge allows the connection of devices on a wired Ethernet network to a wireless network. The bridge acts as the connection point to the Wireless LAN-wireless local area network - (Pronouced as WLAN /W-lan/, or "LAWN" /lorn/, sometimes "WiLAN" /wi-lan/)
A communication system that transmits and receives data using modulated electromagnetic waves, implemented as an extension to, or as an alternative for, a wired LAN. WLANs are typically found within a small client node-dense locale (e.g. a campus or office building), or anywhere a traditional network cannot be deployed for logistical reasons.
Benefits of a Wireless Bridge include user mobility in the coverage area, speed and simplicity of physical setup, and scalability. Being a military spin-off, WLANs also provide security features such as encryption, frequency hopping, and firewalls.
Some of these are intrinsic to the protocol, making WLANs at least as secure as wired networks, and usually more
so. The drawbacks are high initial cost (mostly hardware), limited range, possibility of mutual interference, and the need for security-enable clients.
A communication system that transmits and receives data using modulated electromagnetic waves, implemented as an extension to, or as an alternative for, a wired LAN. WLANs are typically found within a small client node-dense locale (e.g. a campus or office building), or anywhere a traditional network cannot be deployed for logistical reasons.
Benefits of a Wireless Bridge include user mobility in the coverage area, speed and simplicity of physical setup, and scalability. Being a military spin-off, WLANs also provide security features such as encryption, frequency hopping, and firewalls.
Some of these are intrinsic to the protocol, making WLANs at least as secure as wired networks, and usually more
so. The drawbacks are high initial cost (mostly hardware), limited range, possibility of mutual interference, and the need for security-enable clients.
WLAN Architecture for WIFI technology
Station
All components that can connect into a wireless medium in a network are referred to as stations. All stations are equipped with wireless network interface cards (WNICs). Wireless stations fall into one of two categories: access points and clients.
• Access points
Access points (APs) are base stations for the wireless network. They transmit and receive radio frequencies for wireless enabled devices to communicate with.
• Clients
Wireless clients can be mobile devices such as laptops, personal digital assistants, IP phones, or fixed devices such as desktops and workstations that are equipped with a wireless network interface.
All components that can connect into a wireless medium in a network are referred to as stations. All stations are equipped with wireless network interface cards (WNICs). Wireless stations fall into one of two categories: access points and clients.
• Access points
Access points (APs) are base stations for the wireless network. They transmit and receive radio frequencies for wireless enabled devices to communicate with.
• Clients
Wireless clients can be mobile devices such as laptops, personal digital assistants, IP phones, or fixed devices such as desktops and workstations that are equipped with a wireless network interface.
Benefits of WLAN(Wi-Fi technology)
The popularity of wireless LANs is a testament primarily to their convenience, cost efficiency, and ease of integration with other networks and network components. The majority of computers sold to consumers today come pre-equipped with all necessary wireless LAN technology.
The benefits of wireless LANs include:
• Convenience: The wireless nature of such networks allows users to access network resources from nearly any convenient location within their primary networking environment (home or office). With the increasing saturation of laptop-style computers, this is particularly relevant.
• Mobility: With the emergence of public wireless networks, users can access the internet even outside their normal work environment. Most chain coffee shops, for example, offer their customers a wireless connection to the internet at little or no cost.
• Productivity: Users connected to a wireless network can maintain a nearly constant affiliation with their desired network as they move from place to place. For a business, this implies that an employee can potentially be more productive as his or her work can be accomplished from any convenient location.
• Deployment: Initial setup of an infrastructure-based wireless network requires little more than a single access point. Wired networks, on the other hand, have the additional cost and complexity of actual physical cables being run to numerous locations (which can even be impossible for hard-to-reach locations within a building).
• Expandability: Wireless networks can serve a suddenly-increased number of clients with the existing equipment. In a wired network, additional clients would require additional wiring.
• Cost: Wireless networking hardware is at worst a modest increase from wired counterparts. This potentially increased cost is almost always more than outweighed by the savings in cost and labor associated to running physical cables.
Disadvantages
Wireless LAN technology, while replete with the conveniences and advantages described above, has its share of downfalls. For a given networking situation, wireless LANs may not be desirable for a number of reasons. Most of these have to do with the inherent limitations of the technology.
• Security: Wireless LAN transceivers are designed to serve computers throughout a structure with uninterrupted service using radio frequencies. Because of space and cost, the antennas typically present on wireless networking cards in the end computers are generally relatively poor. In order to properly receive signals using such limited antennas throughout even a modest area, the wireless LAN transceiver utilizes a fairly considerable amount of power.
What this means is that not only can the wireless packets be intercepted by a nearby adversary's poorly-equipped computer, but more importantly, a user willing to spend a small amount of money on a good quality antenna can pick up packets at a remarkable distance; perhaps hundreds of times the radius as the typical user. In fact, there are even computer users dedicated to locating and sometimes even cracking into wireless networks, known as wardriver. On a wired network, any adversary would first have to overcome the physical limitation of tapping into the actual wires, but this is not an issue with wireless packets. To combat this consideration, wireless networks users usually choose to utilize various encryption technologies available such as Wi-Fi Protected Access (WPA). Some of the older encryption methods, such as WEP are known to have weaknesses that a dedicated adversary can compromise.
• Range: The typical range of a common 802.11g network with standard equipment is on the order of tens of meters. While sufficient for a typical home, it will be insufficient in a larger structure. To obtain additional range, repeaters or additional access points will have to be purchased. Costs for these items can add up quickly. Other technologies are in the development phase, however, which feature increased range, hoping to render this disadvantage irrelevant.
• Reliability: Like any radio frequency transmission, wireless networking signals are subject to a wide variety of interference, as well as complex propagation effects beyond the control of the network administrator. In the case of typical networks, modulation is achieved by complicated forms of phase-shift keying (PSK) or quadrature amplitude modulation (QAM), making interference and propagation effects all the more disturbing. As a result, important network resources such as servers are rarely connected wirelessly.
• Speed: The speed on most wireless networks (typically 1-108 Mbit/s) is reasonably slow compared to the slowest common wired networks (100 Mbit/s up to several Gbit/s). There are also performance issues caused by TCP and its built-in congestion avoidance. For most users, however, this observation is irrelevant since the speed bottleneck is not in the wireless routing but rather in the outside network connectivity itself.
For example, the maximum ADSL throughput (usually 8 Mbit/s or less) offered by telecommunications companies to general-purpose customers is already far slower than the slowest wireless network to which it is typically connected. That is to say, in most environments, a wireless network running at its slowest speed is still faster than the internet connection serving it in the first place. However, in specialized environments, the throughput of a wired network might be necessary. Newer standards such as 802.11n are addressing this limitation and will support peak throughputs in the range of 100-200 Mbit/s.
Wireless LANs present a host of issues for network managers. Unauthorized access points, broadcasted SSIDs, unknown stations, and spoofed MAC addresses are just a few of the problems addressed in WLAN troubleshooting. Most network analysis vendors, such as Network Instruments, Network General, and Fluke, offer WLAN troubleshooting tools or functionalities as part of their product line.
The benefits of wireless LANs include:
• Convenience: The wireless nature of such networks allows users to access network resources from nearly any convenient location within their primary networking environment (home or office). With the increasing saturation of laptop-style computers, this is particularly relevant.
• Mobility: With the emergence of public wireless networks, users can access the internet even outside their normal work environment. Most chain coffee shops, for example, offer their customers a wireless connection to the internet at little or no cost.
• Productivity: Users connected to a wireless network can maintain a nearly constant affiliation with their desired network as they move from place to place. For a business, this implies that an employee can potentially be more productive as his or her work can be accomplished from any convenient location.
• Deployment: Initial setup of an infrastructure-based wireless network requires little more than a single access point. Wired networks, on the other hand, have the additional cost and complexity of actual physical cables being run to numerous locations (which can even be impossible for hard-to-reach locations within a building).
• Expandability: Wireless networks can serve a suddenly-increased number of clients with the existing equipment. In a wired network, additional clients would require additional wiring.
• Cost: Wireless networking hardware is at worst a modest increase from wired counterparts. This potentially increased cost is almost always more than outweighed by the savings in cost and labor associated to running physical cables.
Disadvantages
Wireless LAN technology, while replete with the conveniences and advantages described above, has its share of downfalls. For a given networking situation, wireless LANs may not be desirable for a number of reasons. Most of these have to do with the inherent limitations of the technology.
• Security: Wireless LAN transceivers are designed to serve computers throughout a structure with uninterrupted service using radio frequencies. Because of space and cost, the antennas typically present on wireless networking cards in the end computers are generally relatively poor. In order to properly receive signals using such limited antennas throughout even a modest area, the wireless LAN transceiver utilizes a fairly considerable amount of power.
What this means is that not only can the wireless packets be intercepted by a nearby adversary's poorly-equipped computer, but more importantly, a user willing to spend a small amount of money on a good quality antenna can pick up packets at a remarkable distance; perhaps hundreds of times the radius as the typical user. In fact, there are even computer users dedicated to locating and sometimes even cracking into wireless networks, known as wardriver. On a wired network, any adversary would first have to overcome the physical limitation of tapping into the actual wires, but this is not an issue with wireless packets. To combat this consideration, wireless networks users usually choose to utilize various encryption technologies available such as Wi-Fi Protected Access (WPA). Some of the older encryption methods, such as WEP are known to have weaknesses that a dedicated adversary can compromise.
• Range: The typical range of a common 802.11g network with standard equipment is on the order of tens of meters. While sufficient for a typical home, it will be insufficient in a larger structure. To obtain additional range, repeaters or additional access points will have to be purchased. Costs for these items can add up quickly. Other technologies are in the development phase, however, which feature increased range, hoping to render this disadvantage irrelevant.
• Reliability: Like any radio frequency transmission, wireless networking signals are subject to a wide variety of interference, as well as complex propagation effects beyond the control of the network administrator. In the case of typical networks, modulation is achieved by complicated forms of phase-shift keying (PSK) or quadrature amplitude modulation (QAM), making interference and propagation effects all the more disturbing. As a result, important network resources such as servers are rarely connected wirelessly.
• Speed: The speed on most wireless networks (typically 1-108 Mbit/s) is reasonably slow compared to the slowest common wired networks (100 Mbit/s up to several Gbit/s). There are also performance issues caused by TCP and its built-in congestion avoidance. For most users, however, this observation is irrelevant since the speed bottleneck is not in the wireless routing but rather in the outside network connectivity itself.
For example, the maximum ADSL throughput (usually 8 Mbit/s or less) offered by telecommunications companies to general-purpose customers is already far slower than the slowest wireless network to which it is typically connected. That is to say, in most environments, a wireless network running at its slowest speed is still faster than the internet connection serving it in the first place. However, in specialized environments, the throughput of a wired network might be necessary. Newer standards such as 802.11n are addressing this limitation and will support peak throughputs in the range of 100-200 Mbit/s.
Wireless LANs present a host of issues for network managers. Unauthorized access points, broadcasted SSIDs, unknown stations, and spoofed MAC addresses are just a few of the problems addressed in WLAN troubleshooting. Most network analysis vendors, such as Network Instruments, Network General, and Fluke, offer WLAN troubleshooting tools or functionalities as part of their product line.
What is WLAN?
A wireless LAN written WLAN is a wireless local area network. This is the linking of two or more computers without using wires. WLAN utilizes a technology based on radio wave to enable communication between devices in a limited area, also known as the basic service set. This gives users the mobility to move around within a broad coverage area and still be connected to the network.
For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops Public businesses such as hotels, offices, coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities.
The first generation of wireless data modems was developed in the early 1980's by amateur radio operators. They added a voice and data communication modem, with data rates below 9600 bit/s, to an existing short distance radio system, typically in the two meter amateur band. The second generation of wireless modems was developed immediately after the FCC announcement in the experimental bands for non-military use of the spread spectrum technology. These modems provided data rates on the order of hundreds of kbit/s. The third generation of wireless modem [then] aimed at compatibility with the existing LANs with data rates on the order of Mbit/s. Several companies [developed] the third generation products with data rates above 1 Mbit/s and a couple of products [had] already been announced [by the time of the first IEEE Workshop on Wireless LANs]."[4]
This was the first time Wireless LAN became publicly available at consumer pricing and easily available for home use. Before the release of the Airport, Wireless LAN was too expensive for consumer use and used exclusively in large corporate settings.
Originally WLAN hardware was so expensive that it was only used as an alternative to cabled LAN in places where cabling was difficult or impossible. Early development included industry-specific solutions and proprietary protocols, but at the end of the 1990s these were replaced by standards, primarily the various versions of IEEE 802.11 WI-FI
For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops Public businesses such as hotels, offices, coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities.
The first generation of wireless data modems was developed in the early 1980's by amateur radio operators. They added a voice and data communication modem, with data rates below 9600 bit/s, to an existing short distance radio system, typically in the two meter amateur band. The second generation of wireless modems was developed immediately after the FCC announcement in the experimental bands for non-military use of the spread spectrum technology. These modems provided data rates on the order of hundreds of kbit/s. The third generation of wireless modem [then] aimed at compatibility with the existing LANs with data rates on the order of Mbit/s. Several companies [developed] the third generation products with data rates above 1 Mbit/s and a couple of products [had] already been announced [by the time of the first IEEE Workshop on Wireless LANs]."[4]
This was the first time Wireless LAN became publicly available at consumer pricing and easily available for home use. Before the release of the Airport, Wireless LAN was too expensive for consumer use and used exclusively in large corporate settings.
Originally WLAN hardware was so expensive that it was only used as an alternative to cabled LAN in places where cabling was difficult or impossible. Early development included industry-specific solutions and proprietary protocols, but at the end of the 1990s these were replaced by standards, primarily the various versions of IEEE 802.11 WI-FI
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