In the wired world, we were able to control the flow of information with physical
restrictions. To gain access to a LAN, someone had to be plugged in, in the building
and near an Ethernet jack. This was no longer the case with a wireless LAN. All
someone needed to do was be within range of the signal. You might be surprised at
just how far a wireless signal carries, in spite of feeling like you need to be in the right
room in your house to get it
just right
sometimes. As an example, my car is joined to
my wireless network in my house so the car can download updates as needed. The car
notifies me when I leave the range of the signal. I can get to the end of my block and
around the corner before I get the notice that my signal is gone. That’s more than half
a dozen homes away from mine.
Along comes Wired Equivalent Privacy (WEP), meant to address the concerns over
sensitive business data leaving the control of the enterprise. As it turns out, the first
pass at protecting data transmitted over wireless using encryption was a bad one.
There have since been other attempts, and the current one is Wireless Protected
Access (WPA) version 2, though that will shortly be replaced by version 3 because of
issues with version 2. It’s these issues, along with various misconfigurations, that
require us to test wireless LANs.
Bluetooth
Not all communication is meant to connect multiple systems together. In fact, the
majority of your communications is probably between your system and your periph‐
erals, whether it’s your keyboard, trackpad, mouse, or monitor. None of these are
meant to be networked; all of them started as wired devices and all are constantly in
communication. To get wires out of the way as much as possible, considering net‐
works were wireless, relieving us of the need to have one other cable tethering us into
place, a wireless protocol was developed in the early 1990s. This protocol used a simi‐
lar set of bandwidth to that later used by 802.11 developed by the mobile device man‐
ufacturer Ericsson.
Today, we know this as
Bluetooth
, and it is used to connect a variety of peripherals. It
does this using profiles that define the functionality being offered by the device. Blue‐
tooth is used for short-range transmissions, typically on the order of about 30 feet.
However, considering what devices use Bluetooth and their need for proximity (you
wouldn’t expect to use a keyboard from a different room, for instance), this isn’t
exactly a limitation. The challenge comes with the power applied to the wireless
transmitter. The more power applied, the farther we can get the signal, so 30 feet isn’t
the maximum; it’s just a common distance.
One issue with Bluetooth is that devices that use it may be easily discoverable by any‐
one interested in probing for them. Devices typically need to pair, meaning they
exchange initial information just to prevent any two devices from connecting ran‐
domly. However, pairing can sometimes be a simple process achieved by asking a
