What come to the module focusing on wireless network standards and security solutions let's start by
going back in time wireless LANs were first introduced in 1991 in the Netherlands over a short period
of time they became globally sought after the working principle behind wireless networks is identical
to the principle of wired networks that we talked about earlier or that of networks transferring data
via optical signals.
They also use the TCAP IP protocol stack fundamental differences in the medium vehicle for transmitting
signal also the signal is no longer electrical or optical.
It uses radio waves instead.
A repercussion of this difference is that unlike wired networks wireless networks share the same carrier
for all computers all hosts that are within the reception range of the transmitter and access point
unlike in wired networks a potential attacker doesn't have to run a man in the middle attack whereas
in the AARP cache or masquerade under a different IP address to eavesdrop on and control transferred
communications establishing an unauthorized connection with a wireless network will remain unnoticed
in most cases.
It's possible to connect to a plane without the need for tampering with the network infrastructure.
It doesn't require a physical presence in the office of a company whose network an intruder tries to
break into any computer connected to an access point shares the medium with the other machines.
This means that the data transferred over the same network including confidential data is in fact public.
This is the key difference that separates wireless and wired networks.
Whenever you connect to a Wi-Fi network can check your mailbox or log into an important system service
or a social media Web site.
You have to be aware that all interconnected users can access your information
security wise.
The worst scenario involves attackers taking control over the access point that can then force you to
connect to the rogue access point.
This situation will be examined more closely in this and the next part of this course
Mel introduced you to wireless communications standards.
Standard two point eleven The Wi-Fi standard is in fact a set of standards
the first eight or two point eleven standard head of maximum data rate of two megabytes per second is
one thing you need to know as far as standards are concerned.
Since Wi-Fi networks are standardized they use the same frequency bands everywhere in the world.
In contrast to CB radio or amateur radio users we don't have to file for a permit to use a particular
frequency spectrum.
The same wireless card used in Europe will also work in the US Asia or Africa.
This is made possible through the implementation of wireless standards.
Your original Ayro two point eleven standard was quite soon replaced with its B version.
This version is fully retroactively compatible
Amendment increases wireless network throughput to 11 megabytes per second
version was released simultaneously with a two point eleven B.
It's quite less popular as it is not compatible with Version B or with the original standard.
Its strength lies in employing a different signalling method.
It also uses a higher frequency the frequencies that can be seen in the chart in the picture or approximates
only because each standard uses a specified number of channels depending on the country.
There can be 11 or 13 channels adjacent channels can overlap.
Neither realize that for example for the B version the frequency is never exactly 2.4 gigahertz successor
B is the standard EDOT two point eleven G.
It's used in business and homeland's even today.
It's retroactively compatible with the B version and the original standard two point eleven g can transmit
data over a relatively long distance with a speed of up to 54 megabytes per second.
Between 2004 and 2005 the end version of the standard was introduced and gained popularity were given
an advantage over the previous versions was the improved reliability and extended range of the wireless
transmission in radio two point eleven n. the same signal can be transmitted and received by multiple
antennas where access points
originally the radio two point eleven standard used not only radio waves to transport data.
It also defined infrared transmission.
The standard however failed to achieve popularity and was supplanted with other technologies.