MCTS 70-680: Wireless Access on Windows 7

Uploaded by itfreetraining on 21.10.2011

Welcome back to your free training course for windows 7. In this video I will look at
wireless networking. First of all I will look at the advantages to wireless networking.
The biggest advantage with wireless is, well it requires no wires. This means no trip hazards.
This makes it great for temporary networks. Wireless may also be your only solution if
you can’t lay cables. This may be because it is too expensive or difficult to lay cables
or maybe you can’t get permission for example with historical buildings.
Of course there are some disadvantages with wireless networking. Wireless network can
suffer from poor signal. This can cause slow performance and loss of service. This can
be caused by many different factors. The distance you are away from your wireless
access point will affect the speed of your transmission. Also other devices can cause
interface for example blue tooth devices, microwaves and other wireless access points.
If you are living in a building with a lot of other people with wireless access points
you will get a lot of interface from their wireless access points. If you use wireless
inside a building like a warehouse, metal structures like cabinets and cause interference.
This will reduce your signal strength and thus the speed and quality of your transmissions.
If you do not secure your wireless device or poorly secure it, anyone within range of
your wireless access point could potential hack into your wireless point and start using
it. Of course there is wireless security you can set up on your wireless access point to
hopefully prevent this from happening. Lastly wireless access points are generally
not as fast as wired networks. The speed of wireless networks has improved over the years
but wired network are still the king when it comes to high transfer rates.
When looking a wireless there are a number of standards. Each standard starts with 802.11
followed by a letter. The first standard is 802.11a. This uses the 5 Ghz range. This allows
speeds up to 54Mbits per second over a small range. This is because the 5Ghz range is easily
absorbed by anything in the way like cabinets or even walls and doors.
The next standard is 802.11b. This standard operates at the 2.4Ghz range. It only
operates at 11Mbits. When it first came out it was great for the home user to access the
internet due to internet speeds at that time not being that high. Transmissions on the
2.4Ghz range go further due to them not being absorbed by walls and other obstacles
as easily. The problem with this range is that it can get interference from other devices
like blue tooth and cordless phones. The next standard is the g standard and again
operators at the 2.4Ghz range. This allows speeds up to 54Mbits per second. Since
it operates on the same frequency as the b standard it suffers from inference from devices
like Bluetooth. The latest standard is the n standard. This
standard can operates on both the 5 and 2.4Ghz range. It boasts that it has a
maximum speed of 600Mbits but there are a lot of reasons while you may not get that
much speed out of it. Firstly to achieve this speed it uses a technology
called mino. This stands for multiple input multiple output. This basically means that
it will transmit over multiple channels at the same time. You can tell a wireless access
point that is using the n standard as generally they have more than one antenna on the device.
A lot of network devices on the market that uses the n standard state they operate up
to 300Mbits. To operate at 600Mbits you need a network device that can transmit 4 signals
at once. The device on the other end must also be able to receive 4 signals at once
and be fast enough to process the signals. This is why you will see some n device on
the market stating they will go up to 300Mbits and not 600Mbits. Regardless of the facts,
even just 300Mbits is a big increase from the g standard.
Before deploying your wireless network the next thing that you want to consider is security
for the network. Without security on your wireless network anyone within range can intercept
your communication and also may be able to listen in on your communication.
The first type of security you can put on your wireless access point is none. This basically
means the wireless access point is open to anyone within range. By default a lot of wireless
modems and wireless devices default to this if not configured. So even if you are not
planning on using wireless on your network device you should disable the wireless or
at least configure security on it. The next type of security is wep. Wep stands
for Wired Equivalent Privacy. When it first came out it was designed to give you the same
security on wireless networks as wired networks. However it has been proven to be very weak
and there are a lot of hacking tools on the internet that will break WEP security.
The next security method you can place on wireless is WPA. This comes in two editions,
the personal edition and the enterprise editions. Essentially the difference is that the personal
edition allows you to configure a password on the device. Anyone with that password can
use the device. The enterprise editions means that request to use the device are authenticated
by a server using radius. The radius server can communicate with other
authentication systems for example active directory. If you need centralized control
over access to the wireless network use the enterprise edition. If you are happy just
having a password on the device use the personal edition.
The next standard is WPA2. This is, as the name suggest, the second edition of WPA. If
you have the choice between the two use WPA2 as it is more secure. Again this comes in
the personal and enterprise editions. The last security that your wireless device
may support is 802.1x. This is a technology that can also be used with wired networks.
If your network is configured with 802.1x, the request to access the wireless network
is sent to a back end server just like the enterprise versions of WPA or WPA2. 802.1x
is used on many networks to allow access to the network with devices like smart cards.
Before I look at how to configure wireless on windows 7, I last want to talk about Ad
hoc and infrastructure networks. Once you start using wireless on windows 7 you can
connect up to an existing network or create your own.
If no network is available you can create your own network called an Ad hoc network.
For example if you meet a friend in a coffee shop and want to share files between the two
computers this is called an Ad hoc network. More computers can join the Ad hoc network
but the important thing to remember is there is no central device controlling access.
The next kind of network you can use with wireless is an infrastructure network. An
infrastructure network is when you have a wireless access point. Either at work, home
or somewhere like an airport or coffee shop. Any computer waiting to use the network goes
through the wireless access point. This tends to be the most common kind of wireless network
used and generally easier to connect to and set up then an Ad hoc network. Let’s now
have a look at how to use wireless on a windows 7 computer.
The first thing I want to do is configure my wireless access point. To configure my
wireless device all I need to do is open the web interface on my wireless device. Once
I am logged in the device I can select the wireless access section.
On the wireless section you can see the name of the wireless access point name otherwise
known as SSID or service set identifier. This name is what appears when your browse of wireless
networks. Notice the option hide SSID. When this is enabled your wireless network name
will not be broadcasted. This was once considered a form of security.
Disabling the SSID was thought to make the network difficult to find unless you know
what to look for. However now days any hacker with any decent amount of skill will still
be able to find the network so this option does little in the way of making your wireless
more secure. If I select the security section I can change
the type of security and encryption used. Some wireless device on the market support
WPS or wi fi protected setup. Using this method allows your wi fi devices to auto configure
themselves. There are a number of ways this can be achieved. Usually WPS uses a pin
number or a button is pressed on the device. To use WPS your network device and your
access point must both support it. Down a bit further you can see that I have
set network authentication to WPA2 personal edition. Personal edition uses a password
which I have entered in below. I would recommend this option if all the devices on your network
support it. If you decide to use WEP, I recommend you
don’t since it is not very secure, you can select either open or shared. If I select
open you can see that by default anyone will be allowed access. If I want to limit access
I can enable WEP. Once enabled the network keys shown will be
used. If you select shared you can see the options are the same. The difference is how
the wireless devices are authenticated. Shared uses a challenge authentication system. This
is considered insecure because a hacker can intercept the challenge request and the response
to the challenge and used them to decrypt the password.
If you must use WEP on your network I would recommend using the open option over the shared
option. The next option is the 802.1X option. When you use this option the authentication
is passed onto a radius server which you can set here. Your radius server may also require
a key to authenticate your device which is entered here.
The next option is WPA. Even though it does not say it, WPA is the enterprise version
and WPA PSK is the personal version. Notice the WPA enterprise version is much the same
as 802.1X. You need to enter in the address of your radius server.
If I select the personal version I only need to enter in a password. Each wireless device
on the network will need to have this password in order to connect up to this wireless access
point. With this device you also have the option of using mixed security which is with
WPA or WPA2. I would recommend using WPA2 only where possible, however if you have
an old device you may need to enable WPA as well.
Down the bottom you have the option to enable TKIP or AES. TKIP was designed to replace
WEP due to it being insecure. Unfortunately since TKIP design is simpler to that of WEP
it also subject to the same kind of attacks as WEP making it insecure. It is still a better
choice than WEP. When given the choice use AES or advanced
encryption standard only. If you have old devices you may need to enable TKIP as well.
In my opinion enabling WPA or WPA2 should be enough security on most networks. One form
of additional security some people use is the MAC filtering. By using this option you
can either allow or deny access based on the MAC or media access control address of the
device. Each network device on the network has a unique
address assigned to it. Using mac filtering it is a simple matter of enabling it and entering
in the device address in here. I would recommend against it because MAC addresses can be faked
and thus this is considered a weak form of security.
If I select the option advanced, this device has a lot of options. I would recommend leaving
them on the default however one particular option in here that may be worth changing
is the channel. This device is currently configured to use channel 4. The device is reporting
that there is a lot of interference on this channel. I would guess that this is caused
by other people in my building having wireless devices on the same channel.
To fix this I will change the channel to channel 6. The device is now reporting a lot less
interference on this channel. If you are finding that you are not getting a high enough through
put on your wireless devices, try changing the channel. This may help.
Now that my wireless access point is configured I will close internet explorer and connect
up to the wireless access point. Down the bottom right hand corner of the screen you
can see a network icon. This will tell you what networks I am currently connected to.
This includes wired, wireless and even vpn connections.
If I left click the icon it will show me what wireless networks are available for me to
connect to. Notice the network at the very top. When I cursor over it I am told some
information about the network adapter. The signal strength is excellent, the security
type is WPA2 personal and the type is 802.11n. As long as you have not disabled the SSID
on your access point your network will appear here. Further down the list is a network with
an exclamation mark next to it. This network does not have a password on it and thus is
not secure. If I look at the network below this one you
will see that it is secured with WEP. In your area you will probably find a few wireless
access points that are not as secure as they could be. I suggest you ask them to watch
this video. Moving back up to the top I can select Extreme
and press connect. I will then be asked for the security key for this network. Notice
the option hide characters which hides the password to prevent someone looking over your
shoulder and getting the password. Once connected I can again click on the network
icon and this time select the option open network and sharing center.
Notice you can now see the wireless network in the network and sharing center. If I select
it you can see information about the network. The most useful information is the signal
strength and the speed it is running at. If I select the details button, you can get a
lot of troubleshooting information. This includes information like the IP address and MAC address
of the wireless network adapter. If I go back and select the option wireless
properties, I can configure additional options for the wireless adapter. By default the wireless
adapter will automatically connect to this network when in range.
On some networks you may have a preferred network. For example if you live next to a
café with free internet you may prefer to have your laptop connect to your home network
even if the signal strength is low. However, when in the cafe your computer will connect
to the free internet if your home network is not available or out of range. You only
need to worry about preferred networks when you have multiple networks in the same area.
The last option connects up to the network point even if the network is not broadcasting
it SSID. This would only occur if it has been switched off. The option down the bottom copies
the configuration of the wireless adapter to a USB flash drive. Using the flash drive
you can move the configuration information to anther laptop. If you are using group policy,
you can import the configuration into group policy. One easy way to configure wireless
in your enterprise is to configure it on one computer, export the configuration and then
apply it your domain using group policy. If I select the security tab I can configure
which security the wireless adapter is using. By default the wireless adapter will automatically
select the highest security available when it is first added. You can also configure
which type of encryption you want to use. If I exit out of here the next part I want
to look at is how to configure an Ad hoc network. An Ad hoc network allows computers to connect
to each other without the use of an access point. To do this select the option set up
a new connection or network. From the wizard select the option at the bottom
set up a wireless Ad hoc network. Once I am past the information screen the configuration
is much the same as setting up an access point. Enter in a name for the network, select the
security that you want to use and enter in a password of the network.
Ad hoc networks are usually set up to be temporary. If you think that you will need the network
again, make sure that you tick the box save this network. That’s it, the Ad hoc network
will now be created. Once created I can close the wizard and select
the option manage wireless networks. This will show me all the wireless networks currently
configured. This includes infrastructure networks as well as Ad hoc networks.
That’s it for wireless networks. Now days with smart phones and touch tablets all supporting
wireless networking you can be sure that wireless is an important topic to understand. In the
next video I will look at the window firewall. To keep you system secure it is essential
to understand the windows firewall. If you want additional study guides and exam questions
make sure you check out our web site.