Tablets and WIFI how to connect and more.
Posted: June 30th, 2012, 10:44 pm
How to connect your Tablet to your home Wifi.
• Identify and open the wireless network settings interface on your tablet. Settings/Wifi
• Make sure the Wifi is turned on, after a few minutes you should see a list of available networks.
• Select your WIFI connection from the list
• This should open a dialog page where you can set the correct security type being used on your network ( you must choose the matching security type on your tablet) and also enter the SSID.
• If you have set up your router with the additional security of only allowing devices by MAC list then you will need to also add the Mac address of your tablet to your router.
• The (MAC) “Media Access Control address” (Not to be confused with the Migration Authority Code needed when you change internet provider) is a unique 12-character identifier (e.g. 00:00:00:00:00:0X) for a specific piece of hardware, like the network adapter located in Wi-Fi devices.
To locate the MAC Address of your Android phone or Android tablet, follow these steps:
1. On the Home screen, tap the Menu key and go to Settings.
2. Scroll down and tap About Tablet then tap Status and then scroll down to view Wi-Fi Mac address
All about ADSL WIFI
Information sourced from: Cnet, Wikipedia, Cisco and Make use of.
What is ADSL
Asymmetric digital subscriber line (ADSL/ADSL+2) is a type of digital subscriber line technology, a data communications technology that enables very fast data transmission over copper telephone lines. Bandwidth (and bit rate) is greater toward the customer premises (known as downstream) than the reverse (known as upstream). This is why it is called asymmetric (having unbalanced properties depending on frequency and the direction of flow).
The PTSN: “Public switched telephone network”, the upstream and the downstream all operate on different frequencies on the same telephone line providing your service.
Bandwidth (and bit rate) is greater toward the customer premises (known as downstream) than the reverse (known as upstream). This is why it is called asymmetric. Providers usually market ADSL as a service for consumers to provide Internet access in a relatively passive mode: able to use the higher speed direction for the download from the Internet but not needing to run servers that would require high speed in the other direction.
Efficiencies for (PPPoA) “Point to point protocol” over (ATM) “Asynchronous Transfer Mode” connections are commonly at best only around 84-87 percent. In addition, some ISPs will have traffic policies that limit maximum transfer rates further in the networks beyond the exchange, and traffic congestion on the Internet, heavy loading on servers and slowness or inefficiency in customers' computers may all contribute to reductions below the maximum attainable. When a wireless access point is used, low or unstable wireless signal quality can also cause reduction or fluctuation of actual speed.
ADSL deployment on an existing plain old telephone service (POTS) telephone line presents some problems because the DSL is within a frequency band that might interact unfavourably with existing equipment connected to the line. Therefore, it is necessary to install appropriate frequency filters at the customer's premises to avoid interference between the DSL, voice services, and any other connections to the line.
Most DSL providers offer a "self-install" option, in which the “internet service provider” (ISP) provides equipment and instructions to the customer. The DSL signal is filtered at each telephone outlet by use of a low-pass filter for voice and a high-pass filter for data, usually enclosed in what is known as a microfilter. This microfilter can be plugged by the end user into any 'phone jack: it does not require any rewiring at the customer's premises.
A side effect of allowing self-install is that the DSL signal can be degraded, especially if more than 5 voiceband (that is, telephone-like) devices are connected to the line. Once a line has had DSL enabled, the DSL signal is present on all telephone wiring in the building, causing attenuation and echo. A way to circumvent this is to go back to the original model, and install one filter upstream from all telephone jacks in the building. Since this requires wiring changes by the customer, and may not work on some household telephone wiring, it is rarely done. It is usually much easier to install filters at each telephone jack that is in use.
DSL signals may be degraded by older telephone lines, surge protectors, poorly-designed microfilters, radio-frequency interference, electrical noise, and by long telephone extension cords. Telephone extension cords are typically made with small-gauge, multi-strand copper conductors which do not maintain a noise-reducing pair twist. Such cable is more susceptible to electromagnetic interference and has more attenuation than solid twisted-pair copper wires typically wired to telephone jacks. These effects are especially significant where the customer's phone line is more than 4 km from the “digital subscriber line access multiplexer” (DSLAM) in the telephone exchange, which causes the signal levels to be lower relative to any local noise and attenuation. This will have the effect of reducing speeds or causing connection failures.
How to get the best from your ADSL broadband WIFI:
Distance from the telephone exchange, cable characteristics, interference from AM radio stations, and local interference and electrical noise at the routers location can adversely affect the signal-to-noise ratio at particular frequencies.
The first thing to check is that your telephone line connection coming into the house and to your router is operating as cleanly and interference free as possible. The distance between the master socket (the incoming telephone line connection) and your router can be critical and if too long can decimate your router’s ability to provide the sorts of speed your ISP has told you should be achievable. In severe case if the distribution wiring from the master socket to your router is too long you may easily halve your potential broadband speed. So wherever possible always keep the amount of wiring between the master socket and your router as short as possible.
If your router is connected adjacent to the master socket (ideal for reducing losses but not always practicable) by a long coiled up lead, consider purchasing or making your own lead which is just long enough to do the job and no longer.
If you have extension telephone sockets and phones in various rooms, the more of these you have the more likely it is to have a deleterious effect on your maximum potential broadband speeds achievable. If practicable, you may consider removing all the slave sockets and their wiring only keeping the master telephone socket, locating your router, microfilter and main telephone closely to it and replacing your older hard-wired telephones with a new base-station and cordless handsets.
This can greatly improve your broadband speeds. The downside is that many cordless phones operate on the same 2.4 GHz frequency as many WIFI systems. It can also be costly and not always possible to locate your router close to your master telephone socket as there is not always a mains supply to hand to supply the necessary electrical power.
In addition, always try to move your router away from any shiny metal objects that emit radio waves -- microwaves, for example, will play havoc with your Wi-Fi signal, as will baby monitors and (believe it or not) Christmas lights. As for what the 'best' channel is, technically, one, six and 11 should yield the best results because they are the only ones far apart enough from each other not to suffer from excessive lapping of other channels.
The only way to find out for sure is to try them all. By careful selection of your router's Wi-Fi channel you may be able to improve the stability, latency and speed of your connection.
Routers operate on a range of different channel frequencies. Most models go up to 11 but some stretch to 13. The most common reason for frustrating disconnections and inconsistent download speeds is when your router and, say, a neighbour's router are broadcasting either on the same channel or on adjacent channels. To change your channel you need to log into your router. To do this you need to find out what the gateway IP address is of your router -- every router has a specific address.
Open your browser and enter [http://192.168.0.1] into your address bar and press enter (not search). This address may be slightly different for various brands depending on exactly which router you have.
Warning: While doing this test, there's a slim chance of hitting a 'dud' channel, in other words, one that picks up so much interference that you won't be able to return to your gateway screen. As a backup, we recommend having a laptop and an Ethernet cable on standby should this unlikely occurrence happen so that you can still log in to your router.
Some of the newer, switch-based WLAN infrastructure products such as BT Home Hub provide a level of RF interference management. With their 802.11 chipsets, these solutions detect the presence of non-802.11 signals. And in response to detection, they can change the 802.11 channel of the APs in the area of the interference. An issue with this approach is that it doesn't solve many of the problems that are out there.
Some interfering devices-for example, Bluetooth devices, cordless phones, 802.11FH devices, jamming emissions) are broadband, so it's not possible to change channels away from them: they are everywhere in the band. And even for devices that operate on a static frequency, it can be challenging to manage channel assignments in a large, cell-based network. In the end, it's critical that you be able to analyze the source of interference-that is, identify what the device is and where it is located-in order to determine the best course of action to handle the interference. In many cases, this "best action" will be removing the device from the premises. In other cases, the response may be to move or shield the device from impacting the network.
Summary: Simple, automated-response-to-interference products are helpful, but they aren't a substitute for understanding the underlying problem.
You can use a Windows application to visually see which channel is least congested and one that I like to use is called “inSSIDer” which gathers information about nearby Wi-Fi networks on any Windows computer without requiring special hardware.
“inSSIDer” scans networks within reach of your computer’s Wi-Fi antenna, tracks signal strength over time, and determines their security settings (including whether or not they’re password-protected).
You can use “inSSIDer” to Inspect your Wi-Fi and surrounding networks, scan and filter hundreds of nearby access points, troubleshoot competing access points and clogged Wi-Fi channels, highlight access points for areas with high Wi-Fi concentration, track the strength of received signals in dBm over time, sort results by MAC Address, SSID, Channel, RSSI, Time Last Seen and export Wi-Fi and GPS data to a KML file in Google Earth. “inSSIDer” is made by Metageek, is widely used and supported and I also like the fact that it is free.
You can download your free copy from here: http://tinyurl.com/7ykrp59
TECHNICAL
– Uses your current wireless card and connection software
– Works with Windows XP, Vista, and 7 (32 and 64 bit)
– Compatible with most GPS devices (NMEA v2.3 +)
Using the visual graphical displays it is easy to see which channel is least congested giving you the choice to switch to it.
Systems that use multiple antennas or smart antennas are able to increase immunity to interference by boosting the desired signal seen at a receiver. When the desired signal is stronger, the ratio of that signal to interference (referred to as signal-to-noise ratio or SNR) is also improved. Effectively, this reduces the zone of interference associated with a particular interference device to a smaller area. But the gain achieved by a smart antenna system is typically only on the order of 10 dB of enhanced signal power.
This means that the range of interference might be shrunk by a factor of 2 over a traditional antenna system, but even then the interference problem is far from solved. For example, if a device would have previously caused problems at a distance of 80 feet from the receiver, it will still cause problems up to 40 feet from the receiver. Thus you would have 5000 square feet of floor space where the interference is still a problem!
Security
Wi-Fi networks are typically locked down with secure access controls, but devices that run on non-Wi-Fi networks, such as Bluetooth devices, are not. A notebook computer with Wi-Fi and Bluetooth connectivity may act as bridge, allowing an intruding device onto your LAN or WLAN.
There are currently three main types of WIFI security being (WEP) Wired Equivalent Privacy , which is one of the least forms of security (WPA) Wi-Fi Protected Access and (WPA2-SPK) Short for Wi-Fi Protected Access 2 - Pre-Shared Key, it is seen to be a much stronger way of securing your network using WPA2 with the use of the optional Pre-Shared Key (PSK) authentication, which was designed for home users without an enterprise authentication server.
To encrypt a network with WPA2-PSK you provide your router not with an encryption key, but rather with a plain-English passphrase between 8 and 63 characters long. Using a technology called TKIP (for Temporal Key Integrity Protocol), that passphrase, along with the network SSID, is used to generate unique encryption keys for each wireless client. And those encryption keys are constantly changed. Although WEP also supports passphrases, it does so only as a way to more easily create static keys, which are usually comprised of the hex characters 0-9 and A-F.
SSID is short for service set identifier, a 32-character unique identifier attached to the header of packets sent over a WLAN that acts as a password when a mobile device tries to connect to the BSS. The SSID differentiates one WLAN from another, so all access points and all devices attempting to connect to a specific WLAN must use the same SSID.
A device will not be permitted to join the (BSS) Basic Service Set unless it can provide the unique SSID.
Because an SSID can be sniffed in plain text from a packet it does not supply any security to the network. An SSID is also referred to as a network name because essentially it is a name that identifies a wireless network.
Wireless networks are, by their nature, less secure than wired ones. While many users overestimate the potential security problems that can stem from a wireless network, there are still some risks that don’t exist with wired options, however minor they may be.
A Quick SSID Intro
The SSID (Service Set Identifier) of a router is the name that it broadcasts to identify itself. This is a feature you’ve already used if you have ever connected to a wireless network, and it helps users separate the many different signals riding the airwaves. When you visit a coffee shop with free Wifi, for example, you usually know the right network to connect to because it is labelled with the shop’s name.
SSIDs are broadcasted voluntarily, however. Every router broadcasts one by default, but the option can be turned off. When you turn off SSID broadcast, others won’t be able to pick up the broadcast of your wireless network and they won’t know to whom the network belongs to.
The Limitations of SSID Hiding
At least, that’s the theory. The problem with SSID hiding is that hiding wireless signals is impossible. SSID or not, your router is still broadcasting radio waves in all directions, which means that those waves can be intercepted. They won’t have an SSID attached to them, but there are other ways to separate wireless networks.
This means that hiding your SSID won’t hide your wi-fi network from someone using a WiFi network scanner. Anyone who is going to try and crack a wireless network will be using one of those anyway, so the utility of hiding an SSID is fairly limited.
If you’re still interested in hiding your SSID, the process of doing so is quite simple.
First, you’ll need to log onto your router. This is done by entering the local IP address of your router into your web browser, in most cases, this is 192.168.0.1. You’ll be presented with a login page prompting you with a username and password. Hopefully you will have customized this, but if not, refer to your router’s manual for the default information.
Once you’re in, navigate to your router’s wireless settings page, find the SSID broadcast option (usually a checkbox) and uncheck it. Then, save your new settings. It’s that easy. Just make sure you know your SSID, because you’ll need to have that information if you want to connect, if you’re not using a Wifi sniffer, at least.
I’ve already said that hiding your SSID isn’t really a method of improving your security, but I want to stress that point. Many people want to know how to hide their SSID, and I can only assume they would want to do so under the assumption that it will make them more secure. Wireless just doesn’t work that way. The only protection this offers is against an uninformed user who is trying to find a specific network, perhaps as a means of identifying where a person lives, or trying to guess the network’s password (you do have a secure password, right?).
Ad-hoc networks
Ad-hoc networks can pose a security threat. Ad-hoc networks are defined as peer-to-peer networks between wireless computers that do not have an access point in between them. While these types of networks usually have little protection, encryption methods can be used to provide security.
The security hole provided by Ad-hoc networking is not the Ad-hoc network itself but the bridge it provides into other networks, usually in the unfortunate default settings in most versions of Microsoft Windows have this feature turned on unless explicitly disabled. Thus the user may not even know they have an unsecured Ad-hoc network in operation on their computer. If they are also using a wired or wireless infrastructure network at the same time, they are providing a bridge to the secured network through the unsecured Ad-hoc connection.
Bridging is in two forms, a direct bridge, which requires the user to actually configure a bridge between the two connections and is thus unlikely to be initiated unless explicitly desired, and an indirect bridge which is the shared resources on the user computer. The indirect bridge provides two security hazards. The first is that critical data obtained via the secured network may be on the user's computer drive and thus exposed to discovery via the unsecured Ad-hoc network.
The second is that a computer virus or otherwise undesirable code may be placed on the user's computer via the unsecured Ad-hoc connection and thus has a route to the secured network. In this case, the person placing the malicious code need not "crack" the passwords to the network; the legitimate user has provided access via a normal and routine log-in. The malefactor simply needs to place the malicious code on the unsuspecting user's system via the open (unsecured) Ad-hoc network.
Identity theft (MAC spoofing)
Identity theft (or MAC spoofing) occurs when a cracker is able to listen in on network traffic and identify the MAC address of a computer with network privileges. Most wireless systems allow some kind of MAC filtering to allow only authorized computers with specific MAC IDs to gain access and utilize the network. However, programs exist that have network “sniffing” capabilities. Combine these programs with other software that allow a computer to pretend it has any MAC address that the cracker desires, and the cracker can easily get around that hurdle.
MAC filtering is effective only for small residential networks, since it provides protection only when the wireless device is "off the air". Any 802.11 device "on the air" freely transmits its unencrypted MAC address in its 802.11 headers, and it requires no special equipment or software to detect it. Anyone with an 802.11 receiver (laptop and wireless adapter) and a freeware wireless packet analyzer can obtain the MAC address of any transmitting 802.11 within range.
Understanding your WIFI
Many people think that the most radio interference comes from other 802.11 b/g/n devices. In reality, the many other types of devices emitting in the unlicensed band dwarf the number of 802.11 devices. These devices include microwave ovens, cordless phones, Bluetooth devices, wireless video cameras, outdoor microwave links, wireless game controllers, Zigbee devices, fluorescent lights, WiMAX, and so on. Even bad electrical connections can cause broad RF spectrum emissions.
These non-802.11 types of interference typically don't work cooperatively with 802.11 devices, and can cause significant loss of throughput. In addition, they can cause secondary effects such as rate back-off, in which retransmissions caused by interference trick the 802.11 devices into thinking that they should use lower data rates than appropriate.
The 802.11 protocol is designed to be somewhat resilient to interference. When 802.11 device senses interference burst occurring before it has started its own transmission, it will hold off transmission until the interference burst is finished. If the interference burst starts in the middle of an ongoing 802.11 transmission (and results in the packet not being received properly), the lack of an acknowledgement packet will cause the transmitter to resend the packet. In the end, the packets generally get through. The result of all these hold-offs and retransmissions, however, is that the throughput and capacity of your wireless network are significantly impacted.
For example, microwave ovens emit interference on a 50 percent duty cycle (as they cycle on and off with the 50-Hz AC power). This means that a microwave oven operating at the same frequency as one of your 802.11 access points can reduce the effective throughput and capacity of your access by 50 percent. So, if your access point was designed to achieve 24 Mbps, it may now be reduced to 12 Mbps in the vicinity of the microwave when it operates.
If your only application on the WLAN is convenience data networking (for example, Web surfing), this loss of throughput may not be immediately obvious. But as you add capacity and latency-sensitive applications such as voice over Wi-Fi your network, controlling the impact of interference will become a critical issue.
The impact of a single interferer on data throughput (or data capacity) of your Wi-Fi network can be astounding. There are three major factors that determine the impact of an interference device:
• Output power. The greater the output power, the larger the physical "zone of interference" the device creates.
• Signal behaviour with respect to time. Analog devices, such as some video cameras and older cordless phones, have a constant always-on signal. Digital devices, such as digital cordless phones, tend to "burst" on and off. Different devices have varying durations of on-time and off-time. In general, the greater the percentage of time that the signal is "on" and the more frequently it bursts, the greater the impact it will have on throughput.
• Signal behaviour with respect to frequency. Some devices operate on a single frequency, and impact specific Wi-Fi channels. Other devices hop from frequency to frequency and impact every channel but to a lesser degree. Some devices, such as microwave ovens and jammers, sweep quickly across the frequency spectrum, causing brief but serious interruptions on many frequencies.
A recent study undertaken by Farpoint Research measured the impact of various interference devices on the data throughput of Wi-Fi. At 25 feet from the AP or client, a microwave oven was found to degrade data throughput by 64 percent, a frequency-hopping phone degraded throughput by 19 percent, and an analog phone and video camera both degraded throughput by 100 percent (in other words, no ability to connect).
Systems that use multiple antennas or smart antennas are able to increase immunity to interference by boosting the desired signal seen at a receiver. When the desired signal is stronger, the ratio of that signal to interference (referred to as signal-to-noise ratio or SNR) is also improved. Effectively, this reduces the zone of interference associated with a particular interference device to a smaller area.
But the gain achieved by a smart antenna system is typically only on the order of 10 dB of enhanced signal power. This means that the range of interference might be shrunk by a factor of 2 over a traditional antenna system, but even then the interference problem is far from solved.
• Identify and open the wireless network settings interface on your tablet. Settings/Wifi
• Make sure the Wifi is turned on, after a few minutes you should see a list of available networks.
• Select your WIFI connection from the list
• This should open a dialog page where you can set the correct security type being used on your network ( you must choose the matching security type on your tablet) and also enter the SSID.
• If you have set up your router with the additional security of only allowing devices by MAC list then you will need to also add the Mac address of your tablet to your router.
• The (MAC) “Media Access Control address” (Not to be confused with the Migration Authority Code needed when you change internet provider) is a unique 12-character identifier (e.g. 00:00:00:00:00:0X) for a specific piece of hardware, like the network adapter located in Wi-Fi devices.
To locate the MAC Address of your Android phone or Android tablet, follow these steps:
1. On the Home screen, tap the Menu key and go to Settings.
2. Scroll down and tap About Tablet then tap Status and then scroll down to view Wi-Fi Mac address
All about ADSL WIFI
Information sourced from: Cnet, Wikipedia, Cisco and Make use of.
What is ADSL
Asymmetric digital subscriber line (ADSL/ADSL+2) is a type of digital subscriber line technology, a data communications technology that enables very fast data transmission over copper telephone lines. Bandwidth (and bit rate) is greater toward the customer premises (known as downstream) than the reverse (known as upstream). This is why it is called asymmetric (having unbalanced properties depending on frequency and the direction of flow).
The PTSN: “Public switched telephone network”, the upstream and the downstream all operate on different frequencies on the same telephone line providing your service.
Bandwidth (and bit rate) is greater toward the customer premises (known as downstream) than the reverse (known as upstream). This is why it is called asymmetric. Providers usually market ADSL as a service for consumers to provide Internet access in a relatively passive mode: able to use the higher speed direction for the download from the Internet but not needing to run servers that would require high speed in the other direction.
Efficiencies for (PPPoA) “Point to point protocol” over (ATM) “Asynchronous Transfer Mode” connections are commonly at best only around 84-87 percent. In addition, some ISPs will have traffic policies that limit maximum transfer rates further in the networks beyond the exchange, and traffic congestion on the Internet, heavy loading on servers and slowness or inefficiency in customers' computers may all contribute to reductions below the maximum attainable. When a wireless access point is used, low or unstable wireless signal quality can also cause reduction or fluctuation of actual speed.
ADSL deployment on an existing plain old telephone service (POTS) telephone line presents some problems because the DSL is within a frequency band that might interact unfavourably with existing equipment connected to the line. Therefore, it is necessary to install appropriate frequency filters at the customer's premises to avoid interference between the DSL, voice services, and any other connections to the line.
Most DSL providers offer a "self-install" option, in which the “internet service provider” (ISP) provides equipment and instructions to the customer. The DSL signal is filtered at each telephone outlet by use of a low-pass filter for voice and a high-pass filter for data, usually enclosed in what is known as a microfilter. This microfilter can be plugged by the end user into any 'phone jack: it does not require any rewiring at the customer's premises.
A side effect of allowing self-install is that the DSL signal can be degraded, especially if more than 5 voiceband (that is, telephone-like) devices are connected to the line. Once a line has had DSL enabled, the DSL signal is present on all telephone wiring in the building, causing attenuation and echo. A way to circumvent this is to go back to the original model, and install one filter upstream from all telephone jacks in the building. Since this requires wiring changes by the customer, and may not work on some household telephone wiring, it is rarely done. It is usually much easier to install filters at each telephone jack that is in use.
DSL signals may be degraded by older telephone lines, surge protectors, poorly-designed microfilters, radio-frequency interference, electrical noise, and by long telephone extension cords. Telephone extension cords are typically made with small-gauge, multi-strand copper conductors which do not maintain a noise-reducing pair twist. Such cable is more susceptible to electromagnetic interference and has more attenuation than solid twisted-pair copper wires typically wired to telephone jacks. These effects are especially significant where the customer's phone line is more than 4 km from the “digital subscriber line access multiplexer” (DSLAM) in the telephone exchange, which causes the signal levels to be lower relative to any local noise and attenuation. This will have the effect of reducing speeds or causing connection failures.
How to get the best from your ADSL broadband WIFI:
Distance from the telephone exchange, cable characteristics, interference from AM radio stations, and local interference and electrical noise at the routers location can adversely affect the signal-to-noise ratio at particular frequencies.
The first thing to check is that your telephone line connection coming into the house and to your router is operating as cleanly and interference free as possible. The distance between the master socket (the incoming telephone line connection) and your router can be critical and if too long can decimate your router’s ability to provide the sorts of speed your ISP has told you should be achievable. In severe case if the distribution wiring from the master socket to your router is too long you may easily halve your potential broadband speed. So wherever possible always keep the amount of wiring between the master socket and your router as short as possible.
If your router is connected adjacent to the master socket (ideal for reducing losses but not always practicable) by a long coiled up lead, consider purchasing or making your own lead which is just long enough to do the job and no longer.
If you have extension telephone sockets and phones in various rooms, the more of these you have the more likely it is to have a deleterious effect on your maximum potential broadband speeds achievable. If practicable, you may consider removing all the slave sockets and their wiring only keeping the master telephone socket, locating your router, microfilter and main telephone closely to it and replacing your older hard-wired telephones with a new base-station and cordless handsets.
This can greatly improve your broadband speeds. The downside is that many cordless phones operate on the same 2.4 GHz frequency as many WIFI systems. It can also be costly and not always possible to locate your router close to your master telephone socket as there is not always a mains supply to hand to supply the necessary electrical power.
In addition, always try to move your router away from any shiny metal objects that emit radio waves -- microwaves, for example, will play havoc with your Wi-Fi signal, as will baby monitors and (believe it or not) Christmas lights. As for what the 'best' channel is, technically, one, six and 11 should yield the best results because they are the only ones far apart enough from each other not to suffer from excessive lapping of other channels.
The only way to find out for sure is to try them all. By careful selection of your router's Wi-Fi channel you may be able to improve the stability, latency and speed of your connection.
Routers operate on a range of different channel frequencies. Most models go up to 11 but some stretch to 13. The most common reason for frustrating disconnections and inconsistent download speeds is when your router and, say, a neighbour's router are broadcasting either on the same channel or on adjacent channels. To change your channel you need to log into your router. To do this you need to find out what the gateway IP address is of your router -- every router has a specific address.
Open your browser and enter [http://192.168.0.1] into your address bar and press enter (not search). This address may be slightly different for various brands depending on exactly which router you have.
Warning: While doing this test, there's a slim chance of hitting a 'dud' channel, in other words, one that picks up so much interference that you won't be able to return to your gateway screen. As a backup, we recommend having a laptop and an Ethernet cable on standby should this unlikely occurrence happen so that you can still log in to your router.
Some of the newer, switch-based WLAN infrastructure products such as BT Home Hub provide a level of RF interference management. With their 802.11 chipsets, these solutions detect the presence of non-802.11 signals. And in response to detection, they can change the 802.11 channel of the APs in the area of the interference. An issue with this approach is that it doesn't solve many of the problems that are out there.
Some interfering devices-for example, Bluetooth devices, cordless phones, 802.11FH devices, jamming emissions) are broadband, so it's not possible to change channels away from them: they are everywhere in the band. And even for devices that operate on a static frequency, it can be challenging to manage channel assignments in a large, cell-based network. In the end, it's critical that you be able to analyze the source of interference-that is, identify what the device is and where it is located-in order to determine the best course of action to handle the interference. In many cases, this "best action" will be removing the device from the premises. In other cases, the response may be to move or shield the device from impacting the network.
Summary: Simple, automated-response-to-interference products are helpful, but they aren't a substitute for understanding the underlying problem.
You can use a Windows application to visually see which channel is least congested and one that I like to use is called “inSSIDer” which gathers information about nearby Wi-Fi networks on any Windows computer without requiring special hardware.
“inSSIDer” scans networks within reach of your computer’s Wi-Fi antenna, tracks signal strength over time, and determines their security settings (including whether or not they’re password-protected).
You can use “inSSIDer” to Inspect your Wi-Fi and surrounding networks, scan and filter hundreds of nearby access points, troubleshoot competing access points and clogged Wi-Fi channels, highlight access points for areas with high Wi-Fi concentration, track the strength of received signals in dBm over time, sort results by MAC Address, SSID, Channel, RSSI, Time Last Seen and export Wi-Fi and GPS data to a KML file in Google Earth. “inSSIDer” is made by Metageek, is widely used and supported and I also like the fact that it is free.
You can download your free copy from here: http://tinyurl.com/7ykrp59
TECHNICAL
– Uses your current wireless card and connection software
– Works with Windows XP, Vista, and 7 (32 and 64 bit)
– Compatible with most GPS devices (NMEA v2.3 +)
Using the visual graphical displays it is easy to see which channel is least congested giving you the choice to switch to it.
Systems that use multiple antennas or smart antennas are able to increase immunity to interference by boosting the desired signal seen at a receiver. When the desired signal is stronger, the ratio of that signal to interference (referred to as signal-to-noise ratio or SNR) is also improved. Effectively, this reduces the zone of interference associated with a particular interference device to a smaller area. But the gain achieved by a smart antenna system is typically only on the order of 10 dB of enhanced signal power.
This means that the range of interference might be shrunk by a factor of 2 over a traditional antenna system, but even then the interference problem is far from solved. For example, if a device would have previously caused problems at a distance of 80 feet from the receiver, it will still cause problems up to 40 feet from the receiver. Thus you would have 5000 square feet of floor space where the interference is still a problem!
Security
Wi-Fi networks are typically locked down with secure access controls, but devices that run on non-Wi-Fi networks, such as Bluetooth devices, are not. A notebook computer with Wi-Fi and Bluetooth connectivity may act as bridge, allowing an intruding device onto your LAN or WLAN.
There are currently three main types of WIFI security being (WEP) Wired Equivalent Privacy , which is one of the least forms of security (WPA) Wi-Fi Protected Access and (WPA2-SPK) Short for Wi-Fi Protected Access 2 - Pre-Shared Key, it is seen to be a much stronger way of securing your network using WPA2 with the use of the optional Pre-Shared Key (PSK) authentication, which was designed for home users without an enterprise authentication server.
To encrypt a network with WPA2-PSK you provide your router not with an encryption key, but rather with a plain-English passphrase between 8 and 63 characters long. Using a technology called TKIP (for Temporal Key Integrity Protocol), that passphrase, along with the network SSID, is used to generate unique encryption keys for each wireless client. And those encryption keys are constantly changed. Although WEP also supports passphrases, it does so only as a way to more easily create static keys, which are usually comprised of the hex characters 0-9 and A-F.
SSID is short for service set identifier, a 32-character unique identifier attached to the header of packets sent over a WLAN that acts as a password when a mobile device tries to connect to the BSS. The SSID differentiates one WLAN from another, so all access points and all devices attempting to connect to a specific WLAN must use the same SSID.
A device will not be permitted to join the (BSS) Basic Service Set unless it can provide the unique SSID.
Because an SSID can be sniffed in plain text from a packet it does not supply any security to the network. An SSID is also referred to as a network name because essentially it is a name that identifies a wireless network.
Wireless networks are, by their nature, less secure than wired ones. While many users overestimate the potential security problems that can stem from a wireless network, there are still some risks that don’t exist with wired options, however minor they may be.
A Quick SSID Intro
The SSID (Service Set Identifier) of a router is the name that it broadcasts to identify itself. This is a feature you’ve already used if you have ever connected to a wireless network, and it helps users separate the many different signals riding the airwaves. When you visit a coffee shop with free Wifi, for example, you usually know the right network to connect to because it is labelled with the shop’s name.
SSIDs are broadcasted voluntarily, however. Every router broadcasts one by default, but the option can be turned off. When you turn off SSID broadcast, others won’t be able to pick up the broadcast of your wireless network and they won’t know to whom the network belongs to.
The Limitations of SSID Hiding
At least, that’s the theory. The problem with SSID hiding is that hiding wireless signals is impossible. SSID or not, your router is still broadcasting radio waves in all directions, which means that those waves can be intercepted. They won’t have an SSID attached to them, but there are other ways to separate wireless networks.
This means that hiding your SSID won’t hide your wi-fi network from someone using a WiFi network scanner. Anyone who is going to try and crack a wireless network will be using one of those anyway, so the utility of hiding an SSID is fairly limited.
If you’re still interested in hiding your SSID, the process of doing so is quite simple.
First, you’ll need to log onto your router. This is done by entering the local IP address of your router into your web browser, in most cases, this is 192.168.0.1. You’ll be presented with a login page prompting you with a username and password. Hopefully you will have customized this, but if not, refer to your router’s manual for the default information.
Once you’re in, navigate to your router’s wireless settings page, find the SSID broadcast option (usually a checkbox) and uncheck it. Then, save your new settings. It’s that easy. Just make sure you know your SSID, because you’ll need to have that information if you want to connect, if you’re not using a Wifi sniffer, at least.
I’ve already said that hiding your SSID isn’t really a method of improving your security, but I want to stress that point. Many people want to know how to hide their SSID, and I can only assume they would want to do so under the assumption that it will make them more secure. Wireless just doesn’t work that way. The only protection this offers is against an uninformed user who is trying to find a specific network, perhaps as a means of identifying where a person lives, or trying to guess the network’s password (you do have a secure password, right?).
Ad-hoc networks
Ad-hoc networks can pose a security threat. Ad-hoc networks are defined as peer-to-peer networks between wireless computers that do not have an access point in between them. While these types of networks usually have little protection, encryption methods can be used to provide security.
The security hole provided by Ad-hoc networking is not the Ad-hoc network itself but the bridge it provides into other networks, usually in the unfortunate default settings in most versions of Microsoft Windows have this feature turned on unless explicitly disabled. Thus the user may not even know they have an unsecured Ad-hoc network in operation on their computer. If they are also using a wired or wireless infrastructure network at the same time, they are providing a bridge to the secured network through the unsecured Ad-hoc connection.
Bridging is in two forms, a direct bridge, which requires the user to actually configure a bridge between the two connections and is thus unlikely to be initiated unless explicitly desired, and an indirect bridge which is the shared resources on the user computer. The indirect bridge provides two security hazards. The first is that critical data obtained via the secured network may be on the user's computer drive and thus exposed to discovery via the unsecured Ad-hoc network.
The second is that a computer virus or otherwise undesirable code may be placed on the user's computer via the unsecured Ad-hoc connection and thus has a route to the secured network. In this case, the person placing the malicious code need not "crack" the passwords to the network; the legitimate user has provided access via a normal and routine log-in. The malefactor simply needs to place the malicious code on the unsuspecting user's system via the open (unsecured) Ad-hoc network.
Identity theft (MAC spoofing)
Identity theft (or MAC spoofing) occurs when a cracker is able to listen in on network traffic and identify the MAC address of a computer with network privileges. Most wireless systems allow some kind of MAC filtering to allow only authorized computers with specific MAC IDs to gain access and utilize the network. However, programs exist that have network “sniffing” capabilities. Combine these programs with other software that allow a computer to pretend it has any MAC address that the cracker desires, and the cracker can easily get around that hurdle.
MAC filtering is effective only for small residential networks, since it provides protection only when the wireless device is "off the air". Any 802.11 device "on the air" freely transmits its unencrypted MAC address in its 802.11 headers, and it requires no special equipment or software to detect it. Anyone with an 802.11 receiver (laptop and wireless adapter) and a freeware wireless packet analyzer can obtain the MAC address of any transmitting 802.11 within range.
Understanding your WIFI
Many people think that the most radio interference comes from other 802.11 b/g/n devices. In reality, the many other types of devices emitting in the unlicensed band dwarf the number of 802.11 devices. These devices include microwave ovens, cordless phones, Bluetooth devices, wireless video cameras, outdoor microwave links, wireless game controllers, Zigbee devices, fluorescent lights, WiMAX, and so on. Even bad electrical connections can cause broad RF spectrum emissions.
These non-802.11 types of interference typically don't work cooperatively with 802.11 devices, and can cause significant loss of throughput. In addition, they can cause secondary effects such as rate back-off, in which retransmissions caused by interference trick the 802.11 devices into thinking that they should use lower data rates than appropriate.
The 802.11 protocol is designed to be somewhat resilient to interference. When 802.11 device senses interference burst occurring before it has started its own transmission, it will hold off transmission until the interference burst is finished. If the interference burst starts in the middle of an ongoing 802.11 transmission (and results in the packet not being received properly), the lack of an acknowledgement packet will cause the transmitter to resend the packet. In the end, the packets generally get through. The result of all these hold-offs and retransmissions, however, is that the throughput and capacity of your wireless network are significantly impacted.
For example, microwave ovens emit interference on a 50 percent duty cycle (as they cycle on and off with the 50-Hz AC power). This means that a microwave oven operating at the same frequency as one of your 802.11 access points can reduce the effective throughput and capacity of your access by 50 percent. So, if your access point was designed to achieve 24 Mbps, it may now be reduced to 12 Mbps in the vicinity of the microwave when it operates.
If your only application on the WLAN is convenience data networking (for example, Web surfing), this loss of throughput may not be immediately obvious. But as you add capacity and latency-sensitive applications such as voice over Wi-Fi your network, controlling the impact of interference will become a critical issue.
The impact of a single interferer on data throughput (or data capacity) of your Wi-Fi network can be astounding. There are three major factors that determine the impact of an interference device:
• Output power. The greater the output power, the larger the physical "zone of interference" the device creates.
• Signal behaviour with respect to time. Analog devices, such as some video cameras and older cordless phones, have a constant always-on signal. Digital devices, such as digital cordless phones, tend to "burst" on and off. Different devices have varying durations of on-time and off-time. In general, the greater the percentage of time that the signal is "on" and the more frequently it bursts, the greater the impact it will have on throughput.
• Signal behaviour with respect to frequency. Some devices operate on a single frequency, and impact specific Wi-Fi channels. Other devices hop from frequency to frequency and impact every channel but to a lesser degree. Some devices, such as microwave ovens and jammers, sweep quickly across the frequency spectrum, causing brief but serious interruptions on many frequencies.
A recent study undertaken by Farpoint Research measured the impact of various interference devices on the data throughput of Wi-Fi. At 25 feet from the AP or client, a microwave oven was found to degrade data throughput by 64 percent, a frequency-hopping phone degraded throughput by 19 percent, and an analog phone and video camera both degraded throughput by 100 percent (in other words, no ability to connect).
Systems that use multiple antennas or smart antennas are able to increase immunity to interference by boosting the desired signal seen at a receiver. When the desired signal is stronger, the ratio of that signal to interference (referred to as signal-to-noise ratio or SNR) is also improved. Effectively, this reduces the zone of interference associated with a particular interference device to a smaller area.
But the gain achieved by a smart antenna system is typically only on the order of 10 dB of enhanced signal power. This means that the range of interference might be shrunk by a factor of 2 over a traditional antenna system, but even then the interference problem is far from solved.