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Archive for the ‘Wireless Networking’ Category

Client Software and Adapter

Any client computer, laptop or wireless device with a compatible wireless client adapter allows connectivity with an access point. The client adapter is a radio transmitter with firmware that supports any of 802.11a/b/g signaling. That is needed before the device can associate and authenticate with the access point. Some access points have a no client mode that doesn’t allow any association from clients extending network distance. Client wireless software included with the adapter must be implemented with specific Windows platforms. The client adapter will be integrated with the laptop, PCMCIA slot or desktop PCI bus slot. They will support specific wireless standards, antenna characteristics, WiFi certification, WDS, network range and security. The wireless manufacturer software must be implemented for all available features.

The following is a list of some client adapter configured settings.

Access Point

As the name suggests an access point allows connectivity between the wireless client or wireless device and the wired network. The access point takes wireless data packets from a client and translates them to standard Ethernet data frames before transmitting across the wired network. Standard category 5 twisted pair cabling will connect the access point Ethernet port with a catalyst switch Ethernet port. The maximum distance between access point and network switch is 100 meters standard with Ethernet design.

WLAN Controllers

Wireless designs with hundreds of root access points on an enterprise network will sometimes deploy wireless LAN controllers. The design specifies lightweight access points connecting to a network switch.

The 4404 WLAN controller device acts as a hub connecting 4 network switches supporting 100 access points. Cisco wireless control system (WCS) wireless network management software is sometimes deployed with WLAN controller design for planning, configuring and optimizing the network.

Power Injector

Cisco access points have a variety of power options such as AC adapters, power over Ethernet and power injectors. The placement of access points is such that in some situations an AC power outlet isn’t available. Should your Ethernet switch not support power over Ethernet, an option such as power injectors extends the distance from an AC outlet. Distances of 1.24 miles are available with a fiber optic media converter.

Power over Ethernet

Cisco access points can be deployed with power over Ethernet (PoE) should the network switch modules support that feature. The distance of 300 feet is the same with Cisco prestandard and 802.3af. The Cisco prestandard use Cat 5 cabling pins 1, 2, 3, 6 for powering devices while 802.3af uses 1, 2, 3, 6 with 10/100/1000BaseT signaling and 4, 5, 7, 8 with 10/100BaseT. Select a network switch module with the power over Ethernet standard your access point has implemented and has a power wattage rating per port for your specific devices. The network switch power supply should be upgraded to support additional power draw from multiple devices. Deploying power over Ethernet will decrease implementation costs with deployment of IPT, wireless and Gigabit. See network switch documents at Cisco web site for information on what network switching modules support PoE and wattage ratings. 802.3af defines powered device class 2 at 3.84W – 6.49W and class 3 at 6.49W – 12.95W.

Power Patch Panel

Cisco inline power patch panels can be deployed where Ethernet switches don’t support power over Ethernet and power injectors aren’t an option. The patch panel does no switching. It powers the devices through a Cat 5 cable that is a maximum 300 feet at a specific rated wattage per port. The patch panel connects the access point to the wired switch with a patch cable.

Connecting to the internet is easy, yet for some people they find it hard to configure networking device such as router in able for them to have wireless connection in their place. Today, a lot of people are now considering WiFi connection in their place, especially that most of the computers that most people want to have are those personal computer such as laptops and notebooks.

Making your place WiFi ready is too easy; as long as you have the right device then you are ready to share your internet connection in your area. Basically, you need modem that is usually being provided by your ISP, from the modem you need a router that has a wireless feature in able for you to have wireless connection in your place.

From the modem, you need a UTP cable that is connected from the Ethernet port of your modem to the wan Ethernet port of your router.

But before you finally connect your laptop wirelessly, you have to configure the settings of your router to enable wireless connection.

At first you need a cable connecting your laptop and your router, and to setup wireless connection you have to load the GUI or Graphic User Interface of your router by entering the default IP address of the router. From there you will the options on how to enable wireless connection by choosing wireless setup. You may need to input SSID or wireless network ID of your router, which will be use as the identification of your network. For the security of your network, you have to enable wireless security and enter WEP key that works as a password of your network, in this way no one will be able to connect into your network unless they know the password of your wireless connection.

Wireless networks (known as Wi-Fi or 802.11 networks) are a fairly recent development, and in the last 10 years or so have brought great convenience to the workplace and to the home. They allow computers to talk to each other, or to access the Internet, using a radio link which is similar to the way cordless phones operate.

They have become progressively faster over the years, and nowadays the speed at which they operate is almost indistinguishable from wired connections.

The drawback to this convenience is that anyone within range can intercept the signal and send or receive on the same bandwidth. What this means to you is that you are at risk in at least 3 areas:

-A hacker can connect to your network and access PCs or laptops connected to it as if they were you. This opens up work or family machines on the network and makes their contents accessible to potentially malicious users.

-A hacker can listen to whatever is being transmitted.

This can include private information, bank account numbers, passwords and other access codes. Under these circumstances, identity theft can easily be perpetrated.

-Even when there is no malicious intent, people can piggy-back on your network and access the Internet by using your access gateway free of charge. This is known as free-loading, or war driving..

Most network equipment is not protected against such interception tactics out of the box, and it is up to you to set up the protection you need by configuring your router or network access device in order to make it secure.

There are basically three things that need to be done in order to make your system secure:

-Encrypt your transmissions.

The WPA and WPA2 standards are best. Your equipment user guide will show you how to set up your configuration so that all transmissions are encrypted. If you are using older equipment which does not handle the WPA standards, then at least use the WEP standard.

-Use a good firewall on all desktop and laptop machines connected to your network. A firewall is a gatekeeper and acts as a barrier between your internal network and the public internet, and performs the function of intercepting and nullifying external threats to your system.

-Use good, strong passwords for every device on your network.

When accessing public networks, such as hotspots in coffee shops, internet cafes, libraries and other public-access wi-fi internet connections, beware of the following:

-Don’t leave the computer unattended.

-Look out for people who “shoulder-surf”, i.e. who try to see your passwords and access codes over your shoulder.

-Some Internet cafes provide each user with a clean disk and a newly installed operating system. These are by far the safest facilities. Try to find and use such highly secure public facilities in your area.

-When you are finished, use the options on your browser to delete cookies, delete temporary internet files, and always clear your history after using a public access internet connection.

-Think about changing your passwords and access codes after using a public internet access facility

-Think twice about carrying out any financial transactions from a hotspot. If it’s not absolutely essential, wait until you get home.

Just a note on passwords. Most of us look at passwords as something tiresome, which we setup and use under protest – an irritating task which we only do when we have to. In fact, passwords are like a lifebelt to a sailor, something whose protection may not be needed often, but when it is, it can save your life.

So there’s a very good argument for not making it easy for the bad guys to guess your password. Once they have it, it opens up your world to them. Passwords can be classified as weak or strong and the weak ones make the hackers job very easy.

Weak passwords are:

-No password at all

-The name of your spouse, children, dates of birth, your pet’s name or your favorite sports team.

-The word “password”. Believe it or not, this is the most common password in the world.

-Short. Less than 7 characters

-Not changed frequently. Change your passwords every couple of months, or more frequently if it’s guarding something very important.

Strong passwords are:

-A combination of letters, numbers and symbols (such as @#$ %&+?>!).

-Longer than 7 characters

-Doesn’t contain easily guessed components such as you name, your company name, your spouse or children’s name etc.

-Changed frequently

-Kept secure. Don’t write them down, don’t email them to anyone. Don’t tell anyone. Don’t use the same password for different services, especially banking sites; If a hacker guesses your password, your whole world is laid bare to him.

So, be careful when using wi-fi internet connections. With just a little thought and preparation you can safeguard yourself, your family and your information.

There are a lot of misconceptions floating around about computer technology. These misconceptions normally come from sources such as a poorly trained sales person or that “computer guru” who lives down the hall from you. Lately, however, I have been seeing more and more shocking misconceptions coming from major technology web sites.

I read an article recently, on a prominent tech web site, which touted how necessary it was for me to own a wireless router. The article left me with the overall impression that wireless networking was way better than wired. A shocking and misleading misconception. Here’s three good reasons why wired networking is better than wireless:

Reason one, speed. Although, wireless data speed standards (like the newly ratified 802.11N standard) are getting faster, they cannot presently beat the data transfer speeds on a wired connection. Moreover, most wireless routers currently in use only go as far as wireless 802.11G standard (54 to 108 Mbps) – and in some cases can’t handle high data transfer rates well. So, for example, if you’re trying to stream a movie, you may encounter playback stuttering (even if you have very high speed broadband) because of your wireless network. As well, data transfer hiccups on a wireless network can occur even when you have features enabled to prevent them, like quality of service (QOS.)

Another factor which can affect wireless network speed is that your wireless router and computer may not like each other. In other words, either due to subtle incompatibilities in hardware, software, firmware or whatever, your wireless router and computer may have trouble communicating. When they do manage to communicate, it is usually at a slower speed than what the devices are rated to communicate at. For instance, I have two netbooks (an HP and a ASUS) which use the same wireless router. The HP netbook connects fine with the router with no problems whereas the ASUS often has issues and sometimes refuses to connect at all. Even though I’ve upgraded the router’s firmware to the latest version, upgraded the wireless device drivers on the ASUS to the latest versions, the problem still exists. This incompatibility factor is not often talked about in regards to wireless networking, but it often can rear its ugly head in exasperating, inexplicable speed issues.

One other major issue that may affect wireless network speed are the types of devices attached to it. Let’s say that you’ve have a 802.11N router with devices attached that are mixed 802.11G/N. There’s a high probability that the router will slow everything down to G rates including the N devices. This is because the router has to best manage the data pathways to all the devices attached to it, which, in some cases, is accomplished by slowing down. Even if everything on your wireless network is N standard, your router may slow itself down to G. This is because some of the newer N routers can detect the close proximity of G networks. If the G networks are too close, your N router may go into a “good neighbor” mode and slow down to G standard.

First bottom line, if you are doing anything which involves moving a lot of data around from computer to computer, a wired connection is the best way to go. As of this writing, there is no consumer wireless networking technology that can beat the speed performance of a 100 Mbps or 1000 Mbps wired network. Wireless networking technology that outstrips wired networking may exist in some government black ops facility (and that would be a secret, so shush) but it does not now exist in the consumer world.

Reason two, stability. A wireless network can be affected by several factors such as distance, radio frequency congestion, etc that can cause anything from slowdowns to dropped connections. Even though your wireless router states its speed as 108 Mbps, the actual speed you get may vary. Many times the actual connection speed may be up to two thirds less than than the rated speed even if you are relatively close to the router. More often, wireless connection speeds may become unstable and vary wildly throughout a computing session. The reasons behind why wireless networks can be unstable are obvious as well as hidden.

A major factor that can affect a wireless network stability is what the routers radio transmission has to travel through to get to you. If, for instance, there are a few walls between your laptop and the wireless router, you may encounter issues such as slow speeds or dropped connections. In other words, you could have a scenario such as this; your wireless router is in your basement and the computer that connects to it is in the den above the basement. Due to the construction of the basement, the router’s signal may be bouncing of the ceiling, barely making it to the computer, and thereby causing connection problems.

What your wireless router has to compete with also affects wireless networking stability. Most wireless routers transmit on the 2.4 GHz radio frequency. This is the same frequency that Bluetooth, many cordless phones or devices such as microwave ovens emit RF on. So, for example, if someone in your house turns on the microwave to pop some popcorn, your wireless network may drop dead in the process! To overcome this, you may be tempted to try the 802.11A standard which uses the 5.8 GHz radio frequency. You would quickly find (as have I) that this may not work either. Although, your 802.11A network would be safe from your microwave oven, it still would suffer from stability problems. The 5.8 GHz radio frequency has shorter wavelengths than the 2.4 GHz frequency. Simply put, a shorter radio wavelength means less distance traveled and more difficulty penetrating things (like walls) by the radio signal.  Consequently, you’d still be stuck with stability problems, no matter which standard was used, A or G.

Competition that your wireless router has to contend with, and which again affects stability, comes in forms other than a microwave. If you live in a typical neighborhood, like mine, there may be upwards twenty other homes that have wireless networks. Your network as well as your neighbor’s network are competing for the same radio spectrum space and radio channels. To put it in another way, your wireless data is doing a commute from a to b, similar to your commute back and forth to work. Just like there is sometimes roadway congestion often times preventing your timely arrival to work, the same thing happens in the wireless networking world. Also just as the weather can affect your real world commute, weather can affect wireless networking. Weather conditions can actually boost the effective range of a wireless signal. When this happens in a already wireless congested neighborhood, chances are that you will encounter stability problems.

Second bottom line, wired networks provide consistently better stability and are much less prone to slowdowns or dropped connections. As well, a wired network suffers none of the issues that wireless does, like radio frequency congestion or interference. So in other words, with a wired network, your kids can use the microwave to pop popcorn while you do your computing in peace. As well, you don’t have to worry about your neighbor crowding you out radio spectrum wise when the weather conditions are just right.

Reason three, security. A wireless network, because of its very nature, is easier to hack than a wired network. Although, a wireless router may be properly set up in terms of it’s firewall, security encryption and MAC filtering, it’s still broadcasting over the air. Anyone with a laptop loaded with the appropriate software can detect and hack wireless signals. Moreover, every current wireless security protocol can be now overcome by a hacker. In another analogy, a wireless network is like a wireless door to your house. As with the physical doors to your home, a determined hacker can kick in your wireless door. And once a miscreant gains access to your wireless network, they have access to everything attached to your network, wired or wireless. For instance, your neighbor who lives three doors down from you (who has successfully hacked into your wireless network), may be using your web-cam to spy on you! That same deviant, hacker neighbor of your’s (who may not be thrilled about how you look on the webcam), may also be stealing your broadband bandwidth for sole the purpose of surreptitiously downloading something like porn. Due to their illegal activity, on your wireless network, you get stuck with angry emails from your ISP – and – quite possibly a visit from the police! Consider too, that your wireless network can be hacked by someone who does not live in your neighborhood. Some of the more recent commercial data breaches happened due to someone driving around in a car and detecting wireless signals. In one case, the criminals just simply sat outside of stores in their cars with laptops and hacked into the wireless networks of the businesses where they detected a signal. The same type of thing is being done in residential neighborhoods – so yes, it can happen to you!

Third and final bottom line, a wired network is harder to break into. Since again, nothing is being broadcast over the air, the only access point that a hacker can try is the firewall in a wired only router. I’m not saying that a wired router can’t be hacked, it’s just that it’s more difficult to do so.

So if you’re considering setting up a computer network, and have to choose between wired or wireless, go with wired. Particularly, again, if you are doing anything that involves moving a lot of data around, like streaming movies from your media server to your home theater computer. If you do need wireless for a device like a iPod touch, consider getting a wireless access point for your wired network. BTW, if a wireless access point cannot be had, a wireless router can function as a AP, just by disabling its router functionality.

I know that there are cases where a wired network is impractical, thus, leaving you with wireless as the only option. As with anything in life, that’s the breaks, and you go with the only option that is available to you. If, however, the opportunity presents itself for you to construct a wired network (either through a new home construction, house rewire, or plain Jane do it yourself sweat equity) by all means take that opportunity. While you’re going about the business of building your wired network, remember also to ignore the naysayers who complain about the mess of wires. Again, as with everything in life, there are solutions to make a wired network neat while maintaining its functionality.

Which ever way you go, wired or wireless, make sure everything is setup properly security wise. Also, don’t be lulled into thinking that wireless is better than wired networking, no matter which prominent technology web site says so.

Many wireless network adapters install and present a different software by default, deactivating Windows’ one in the process, to allow you to configure and connect to wireless networks. Unfortunately they are often inadequate compared to Windows’ own configuration interface (believe it or not). This tutorial will show you how to revert back to the normal Windows wireless network configuration software to manage your connection.

To access Windows’ wireless network configuration utility and check if Windows is being used to configure wireless network connectivity:

Click on the start menu.
Go to “Settings” and click on “Network Connections”.
Click on “Wireless network connection” in the window that appears.

If Windows is not configuring your wireless network it will say so in the “Wireless Network Connection” window that appears. The message should, unsurprisingly, read:

“Windows cannot configure this wireless connection. If you have enabled another program to configure this wireless connection, use that software”.

To allow Windows to configure your wireless network connection follow these steps:

Go to Control panel and click on “Administrative Tools”
Click on “Services” in the new window
A window with a list of all services will show up. Find “Windows Zero Configuration” service in the list and double click on it.
Click on “Start” if the status says the service is stopped.
Now go back to the Windows wireless network connection window (steps shown above) and click on the “Change advanced settings“ link on the left.
Click on the “Wireless Connection” tab on the top of the window.
At the top of the window there should be a check-box reading “Use Windows to configure my wireless network settings.” Check this box and press “Ok”.

You’re done!