Wireless LAN (WLAN) is a wireless broadband technology that utilizes radio frequency (RF) to transmit and receive data through the air, minimizing the need for wired networks.
There are two competing RF technologies in the use of Wireless LAN, the IEEE 802.11 standard and proprietary technologies. Both fall under wireless broadband technology. Broadband means the ability to transmit high-speed voice, data and video traffic using a wide range of frequencies on a single wireless medium or device.
This page aims to give you an overview about Wireless Broadband -IEEE 802.11 standard commonly called Wireless LAN. 802.11 is a standard agreed by the IEEE (Institute of Electrical and Electronics Engineers, Inc.) the world's leading professional association for the advancement of technology. 802.11 is the standard adopted by IEEE to define an over the air interface between a wireless client and base station or between two wireless clients.
The 802.11 standard has evolved over the years and became one of the most successfully deployed technologies. The standard now covers 802.11b, 802.11a and 802.11g systems.
Radio Frequency (RF) is the medium use by wireless networks in the transmission of information over the air. RF works by converting electrical current into radio waves and transmit those waves over the air using a defined frequency of the radio spectrum. An example, the AM and FM radios two most commonly known uses of the RF spectrum.
The Federal Communications Commission (FCC) is the one administering the use of radio spectrum between the frequencies of 9 Kilohertz (KHz) and 300 gigahertz (GHz). 802.11 WLAN systems operate in the radio spectrum available to the public, also known as the unlicensed frequency band. These radio spectrum bands are unlicensed, free for use by anyone provided FCC regulations are complied with.
The FCC as a regulatory governs the maximum transmit power of wireless radios as well as, type of encoding and frequency modulations to be used. In 802.11 operations, it is provided for by the FCC that non-licensed radios (such as 802.11) must accept interference from licensed electronic systems. FCC considers licensed device as the primary equipment.
802.11 Wireless LAN Standard Operating Frequencies: The 802.11 standard are assigned frequencies 2.4 GHz (2.4-2.4835 GHz) on ISM Band and 5 GHz (5.15-5.25 GHz, G.25-5.35 GHz, 5.725-5.825 GHz) of the U-NII band. 802.11b and 802.11g operates on 2.4 GHz while 802.11a is operating on the 5 GHz band.
802.11 assigned frequency range has different characteristics. Lower Frequencies (2.4 GHz ) exhibit better range but with limited bandwidth and lower data rates. Higher Frequencies (5 GHz) have less range but higher data rates but is prone to blocking by solid objects.
These are attributable to attenuation and interference. Attenuation or the loss of signal strength during transmission is higher when the receiver is farther from the transmitter. Obstacles such as mountains and buildings also contribute to attenuation by blocking or weakening radio signals, causing signal loss or dead spots. Depending of what they are made of, floors, walls, and ceilings can either strengthen or weaken WLAN signals. Interference can be caused by nearby stations operating in the same frequency on the same channel. 2.4 GHz cordless phones for instance can cause great interference on 802.11b wireless networks.
Wireless broadband and WLAN devices are called transceiver devices since it both transmit and receive at the same time. Each component both transmits and receives IP traffic. Antennas direct RF power into the air over a coverage area. An Antenna provides wireless LAN devices gain, direction and polarization. Gain is the measure of increase in power while direction is the shape of the transmission pattern. Polarization is dependent on antenna alignment and can be typically described as vertical or horizontal. Most Access Point antennas are designed to operate in vertical pattern for maximum horizontal coverage plane or polarization. Putting the antenna in a horizontal position will result in a vertical plane limiting coverage.
The factor to consider in increasing the range of Wireless LAN devices is the Antenna and EIRP. EIRP or Equivalent Isotropically Radiated Power is being governed or limited by FCC regulations to a maximum of Four (4) watts with additional restrictions/limitations depending on type of antenna (directional or omni-directional) and antenna placement (indoor or outdoors). Some countries limit EIRP to as much as 100mw, above this will require a license to operate. This applies mostly for outdoor WLAN equipments.
To deploy long-range outdoor wireless broadband and WLAN devices, please consult your country’s telecommunication commission guidelines on use of outdoor wireless broadband (WLAN) devices.
The goal is to reach people yearning to start their own home-based business even in remote regions thru cost-effective internet business and long-range wireless communication solutions.
By: Allan Ampoloquio
Saturday, December 20, 2008
Wireless Router & Security: A Step-By-Step Guide
Setting up a wireless router is easy. Essentially you turn your cable or DSL modem off and your wireless router on. Then, you connect the router to the modem with a cable, and turn the modem back on. You are more or less done. The wireless network wizard on your computer will pick up the router and, if your ISP does not have any special requirements, away-you-go, you are on the Internet.
For ease of setup and configuration, manufacturers ship wireless routers with all security disabled. Therein lies the problem. If you do not take any further steps to secure your router, and a surprising number of people don’t, your network will be wide open to all passersby and strangers. It’s like you’ve hung out a sign, “The door is open. Please come in and help yourself.”
The problem is not that strangers will be able to use your router to access the Internet but that, without further protection, would-be intruders will be able monitor and sniff out information you send and receive on your network. Malicious intruders can even hop on to your internal network; access your hard drives; and, steal, edit, or delete files on your computer.
The good news is that it is relatively easy to secure your wireless router. Here are three basic steps you should take.
1. Password protect the access to your router’s internal configuration
To access your router’s internal setup, open a browser and enter the routers setup URL. The URL will be specified in the manual. The URLs for D-Link and Linksys routers, two major manufacturers of wireless routers, are http://192.168.0.1 and http://192.168.1.1, respectively.
For Linksys routers, leave the user name blank and type “admin” (without the quotes) in the password field and press enter. To change the password, simply click on the Password tab and enter your new password.
For other routers, please consult your manual. Alternately, you can search on the Internet with the term “default login for ”. Don’t be surprised to find quite a number of pages listing default login parameters for many different routers, even uncommon ones.
2. Change the default SSID (Service Set IDentifier)
The SSID is the name of a WLAN (Wireless Local Area Network). All wireless devices on a WLAN use SSIDs to communicate with each other.
Routers ship with standard default SSIDs. For example, the default SSID for Linksys routers is, not unsurprisingly, “Linksys”. As you can see, if you don’t change the default SSID of your router a would-be intruder armed with a few common SSIDs from major manufacturers will be able to find your wireless network quite easily.
To change the SSID, click on the Wireless tab. Look for an input item labeled SSID. It will be near the top. Enter a new name for network. Don’t use something like “My Network”. Use a name that is be hard to guess.
3. Disable SSID broadcast
Wireless enabled computers use network discovery software to automatically search for nearby SSIDs. Some of the more advanced software will query the SSIDs of nearby networks and even display their names. Therefore, changing the network name only helps partially to secure your network. To prevent your network name from being discovered, you must disable SSID broadcast.
In the same screen that you changed the name of your network, you will see options for SSID broadcast. Choose “Disable SSID” to make your network invisible. Now save all your settings and log out.
Since your wireless network is now invisible, you will have to configure your computers to connect to your wireless network using the new name. On Windows XP, start by clicking on the wireless icon in the Notification Area and proceed from there.
With these three steps, your network now has basic security. However, if you keep sensitive information on your computers, you may want to secure your wireless network even further. For example, you can
- Change the channel your router uses to transmit and receive data on a regularly basis.
- Restrict devices that can connect to the router by filtering out MAC (Media Access Control) addresses.
- Use encryption such as WEP and WPA.
As with most things in life, security is a trade off between cost (time, money, inconvenience) and benefit (ease of use). It is a personal decision you make. However for the majority of home uses, the three basic steps plus WEP/WPA encryption provides reasonably strong security.
Turning on encryption is a two-step process. First you configure your router to use encryption using an encryption key of your choice. And then, you configure your computer to use the encryption key. The actual process of configuring your router for encryption varies from router to router. Please consult the router’s manual.
There are even stronger methods for ensuring security. A strong and robust security method is RADIUS (Remote Authentication Dial In User Service). Using RADIUS requires additional hardware and software. However, there are companies that offer RADIUS security as a subscription based service. The fees are reasonable and dropping.
Therefore for example, if you run a business on your wireless network, have sensitive data on your computers such as credit card information, and have a number of users who access your network, you should consider using RADIUS. Since the service sector for RADIUS is dynamic and growing, a search on the Internet with terms like “RADIUS subscription” or “RADIUS service” is probably the best way to locate one.
By: Brian Medini
For ease of setup and configuration, manufacturers ship wireless routers with all security disabled. Therein lies the problem. If you do not take any further steps to secure your router, and a surprising number of people don’t, your network will be wide open to all passersby and strangers. It’s like you’ve hung out a sign, “The door is open. Please come in and help yourself.”
The problem is not that strangers will be able to use your router to access the Internet but that, without further protection, would-be intruders will be able monitor and sniff out information you send and receive on your network. Malicious intruders can even hop on to your internal network; access your hard drives; and, steal, edit, or delete files on your computer.
The good news is that it is relatively easy to secure your wireless router. Here are three basic steps you should take.
1. Password protect the access to your router’s internal configuration
To access your router’s internal setup, open a browser and enter the routers setup URL. The URL will be specified in the manual. The URLs for D-Link and Linksys routers, two major manufacturers of wireless routers, are http://192.168.0.1 and http://192.168.1.1, respectively.
For Linksys routers, leave the user name blank and type “admin” (without the quotes) in the password field and press enter. To change the password, simply click on the Password tab and enter your new password.
For other routers, please consult your manual. Alternately, you can search on the Internet with the term “default login for ”. Don’t be surprised to find quite a number of pages listing default login parameters for many different routers, even uncommon ones.
2. Change the default SSID (Service Set IDentifier)
The SSID is the name of a WLAN (Wireless Local Area Network). All wireless devices on a WLAN use SSIDs to communicate with each other.
Routers ship with standard default SSIDs. For example, the default SSID for Linksys routers is, not unsurprisingly, “Linksys”. As you can see, if you don’t change the default SSID of your router a would-be intruder armed with a few common SSIDs from major manufacturers will be able to find your wireless network quite easily.
To change the SSID, click on the Wireless tab. Look for an input item labeled SSID. It will be near the top. Enter a new name for network. Don’t use something like “My Network”. Use a name that is be hard to guess.
3. Disable SSID broadcast
Wireless enabled computers use network discovery software to automatically search for nearby SSIDs. Some of the more advanced software will query the SSIDs of nearby networks and even display their names. Therefore, changing the network name only helps partially to secure your network. To prevent your network name from being discovered, you must disable SSID broadcast.
In the same screen that you changed the name of your network, you will see options for SSID broadcast. Choose “Disable SSID” to make your network invisible. Now save all your settings and log out.
Since your wireless network is now invisible, you will have to configure your computers to connect to your wireless network using the new name. On Windows XP, start by clicking on the wireless icon in the Notification Area and proceed from there.
With these three steps, your network now has basic security. However, if you keep sensitive information on your computers, you may want to secure your wireless network even further. For example, you can
- Change the channel your router uses to transmit and receive data on a regularly basis.
- Restrict devices that can connect to the router by filtering out MAC (Media Access Control) addresses.
- Use encryption such as WEP and WPA.
As with most things in life, security is a trade off between cost (time, money, inconvenience) and benefit (ease of use). It is a personal decision you make. However for the majority of home uses, the three basic steps plus WEP/WPA encryption provides reasonably strong security.
Turning on encryption is a two-step process. First you configure your router to use encryption using an encryption key of your choice. And then, you configure your computer to use the encryption key. The actual process of configuring your router for encryption varies from router to router. Please consult the router’s manual.
There are even stronger methods for ensuring security. A strong and robust security method is RADIUS (Remote Authentication Dial In User Service). Using RADIUS requires additional hardware and software. However, there are companies that offer RADIUS security as a subscription based service. The fees are reasonable and dropping.
Therefore for example, if you run a business on your wireless network, have sensitive data on your computers such as credit card information, and have a number of users who access your network, you should consider using RADIUS. Since the service sector for RADIUS is dynamic and growing, a search on the Internet with terms like “RADIUS subscription” or “RADIUS service” is probably the best way to locate one.
By: Brian Medini
Understanding Wireless Lan Networking And Long-range Wireless Lan Communication
Understanding wireless and wireless LAN networking enable you to properly plan and design the effective deployment of wireless networks be it home-networking or using outdoor long-range WLAN for rural internet connectivity.
Wireless networking allows computers and peripherals to communicate using radio frequency (RF) transmissions rather than over conventional network cabling. Using wireless Ethernet adaptors, any device capable of being used on a regular computer network can be accessed over a wireless connection for task ranging from file and printer sharing to multimedia and internet access.
Wireless Ethernet Technology is outlined by a set of standards called IEEE 802.11. Although other wireless technologies and protocols exist, the term wireless is generally used in reference to the IEEE 802.11 standards.
The communication protocols for wireless networking are defined by the Institute of Electrical Engineers (IEEE) 802.11 standard, which incorporates the 802.11a, 802.11b and 802.11g protocols (although other standards are in progress). The most widely used of these is 802.11b (Wireless-B), which is more reliable than the faster 802.11a (Wireless-A) standard, and is more cost-effective to produce and operate as well. Wireless-G or 802.11g, is a newer protocol that is becoming more widely adopted by vendors as it is capable of speeds up to 54Mbps rather than the 11Mbps of 802.11b devices.
It is no longer rare to find devices that support all three standards, but generally, Wireless-G is designed to be backwards compatible with Wireless-B devices. Thus Wireless-B and Wireless-A devices will not work with each other, and neither are they compatible with Wireless-G devices.
Some manufacturers offer models with dual-band (Wireless A & G/B) auto-switch mode for greater communication flexibility. Network planners can plan their network deployment by using a combination of Wireless-B,G or A.
Wireless 802.11 standard utilizes the license-free radio frequency bands around the 2.4GHz and/or 5GHz ranges. The 802.11b and 802.11g protocols use the 2.4GHz band whereas 802.11a uses the 5GHz band. Wireless-B is by far the most popular standard, with the newer Wireless-G (802.11g) and Wireless-A (802.11a) closing in fast.
Wi-FI or Wireless Fidelity is a certification program established by the Wi-Fi Alliance to ensure interoperability of wireless devices. Originally, the term Wi-Fi was intended to be interchangeable with 802.11b, but more recently it has broadened to cover any 802.11 network.
WLAN or Wireless Local Area Network, is a computer network –or part thereof- that incorporates wireless devices. In a WLAN network, a conventional LAN set-up can be extended to include wireless devices using an access point. Although wireless networks can be completely independent of conventional network, WLAN usually forms part of an existing wired network.
Wireless Transmission ranges vary greatly and lowering the bandwidth will increase the coverage area, a standard 802.11b or 802.11g device will typically have a range of about 30m indoor and up to 120m line-of-sight outdoors. The main reason for the variance between indoors and line-of-sight coverage is that walls and other objects do impede the wireless signal. Because wireless transmissions are actually low frequency radio waves, they will pass through walls and other solid matter relatively easy. As distance increases, the throughput decreases. This is because lower signal strength result in dropped packets and result in a general decrease in network efficiency.
Understanding the technology in wireless and wireless LAN/WAN networking allows the planner the flexibility of using wired and wireless networks. There are areas that wired networks can not go owing to distance, terrain or topography thus if the planner has knowledge on wireless LAN networking, the simpler, faster and easy it is to deploy an effective wireless network.
Understanding how wireless LAN works will also help you plan deployment of a rural wireless internet access service. Wireless LAN is a very cost-effective solution for much needed internet connectivity requirements in far, remote villages. WISP is a good and potential business in remote areas.
Either you use commercial "off-the-shelf" WLAN gadget, tweak and improve its performance by using higher-gain outdoor antenna or buy a true-outdoor long-range Wireless LAN. For assured network performance, service-quality and less network downtime, we recommend using the latter.
The goal is to reach people yearning to start their own home-based business even in remote regions thru cost-effective internet business and long-range wireless communication solutions.
By: Allan Ampoloquio
Wireless networking allows computers and peripherals to communicate using radio frequency (RF) transmissions rather than over conventional network cabling. Using wireless Ethernet adaptors, any device capable of being used on a regular computer network can be accessed over a wireless connection for task ranging from file and printer sharing to multimedia and internet access.
Wireless Ethernet Technology is outlined by a set of standards called IEEE 802.11. Although other wireless technologies and protocols exist, the term wireless is generally used in reference to the IEEE 802.11 standards.
The communication protocols for wireless networking are defined by the Institute of Electrical Engineers (IEEE) 802.11 standard, which incorporates the 802.11a, 802.11b and 802.11g protocols (although other standards are in progress). The most widely used of these is 802.11b (Wireless-B), which is more reliable than the faster 802.11a (Wireless-A) standard, and is more cost-effective to produce and operate as well. Wireless-G or 802.11g, is a newer protocol that is becoming more widely adopted by vendors as it is capable of speeds up to 54Mbps rather than the 11Mbps of 802.11b devices.
It is no longer rare to find devices that support all three standards, but generally, Wireless-G is designed to be backwards compatible with Wireless-B devices. Thus Wireless-B and Wireless-A devices will not work with each other, and neither are they compatible with Wireless-G devices.
Some manufacturers offer models with dual-band (Wireless A & G/B) auto-switch mode for greater communication flexibility. Network planners can plan their network deployment by using a combination of Wireless-B,G or A.
Wireless 802.11 standard utilizes the license-free radio frequency bands around the 2.4GHz and/or 5GHz ranges. The 802.11b and 802.11g protocols use the 2.4GHz band whereas 802.11a uses the 5GHz band. Wireless-B is by far the most popular standard, with the newer Wireless-G (802.11g) and Wireless-A (802.11a) closing in fast.
Wi-FI or Wireless Fidelity is a certification program established by the Wi-Fi Alliance to ensure interoperability of wireless devices. Originally, the term Wi-Fi was intended to be interchangeable with 802.11b, but more recently it has broadened to cover any 802.11 network.
WLAN or Wireless Local Area Network, is a computer network –or part thereof- that incorporates wireless devices. In a WLAN network, a conventional LAN set-up can be extended to include wireless devices using an access point. Although wireless networks can be completely independent of conventional network, WLAN usually forms part of an existing wired network.
Wireless Transmission ranges vary greatly and lowering the bandwidth will increase the coverage area, a standard 802.11b or 802.11g device will typically have a range of about 30m indoor and up to 120m line-of-sight outdoors. The main reason for the variance between indoors and line-of-sight coverage is that walls and other objects do impede the wireless signal. Because wireless transmissions are actually low frequency radio waves, they will pass through walls and other solid matter relatively easy. As distance increases, the throughput decreases. This is because lower signal strength result in dropped packets and result in a general decrease in network efficiency.
Understanding the technology in wireless and wireless LAN/WAN networking allows the planner the flexibility of using wired and wireless networks. There are areas that wired networks can not go owing to distance, terrain or topography thus if the planner has knowledge on wireless LAN networking, the simpler, faster and easy it is to deploy an effective wireless network.
Understanding how wireless LAN works will also help you plan deployment of a rural wireless internet access service. Wireless LAN is a very cost-effective solution for much needed internet connectivity requirements in far, remote villages. WISP is a good and potential business in remote areas.
Either you use commercial "off-the-shelf" WLAN gadget, tweak and improve its performance by using higher-gain outdoor antenna or buy a true-outdoor long-range Wireless LAN. For assured network performance, service-quality and less network downtime, we recommend using the latter.
The goal is to reach people yearning to start their own home-based business even in remote regions thru cost-effective internet business and long-range wireless communication solutions.
By: Allan Ampoloquio
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