In the last video we discussed about the past two attacks in this video, we are going to discuss about
the two attacks and the attack attempts to alter system resources or affect their operations.
An attack involves some modification of datastream or creation of false statements, types of attacks,
a masquerade repudiation, ripply and denial of service.
The first attack is muscular, muscular attack takes place within one entity, pretends to be a different
entity.
Consider the same three characters, Bob Ellis and Judy here.
Bob since Mr. to Alice.
Hey, Alice.
It's me, Bob.
How are you?
Alice replies, Hey, Bob, I'm fine.
What's up?
But in this case, the Trudy, who is the interceptor, impersonates Bob and sends a message to Alice.
How about Robert at 5:00 p.m.?
This message is not sent through, Bob, but this message is sent to Trudy.
Who is the intruder?
Alice replies, Okay, Bob then.
And this creates a confusion which lets Alice into trouble.
This is called as the masquerade attack.
Next is the replay, and it involves the best capture of a message and subsequent transmission to produce
an opposite effect.
Consider the scenario, Bob Ellis and Judy here.
Bob, since Mesoscale is here.
Let's meet today at six p.m. a little place.
Hey, Bob.
OK.
But now Trudy impersonates Bob and sends the message.
Here is let's meet today at six p.m. Alissa gets confused and again, replace Bob.
I already told you, OK, I will come.
But this creates confusion.
Rather, this is a very simple case of replanning.
Now, for the same example, let us consider the scenario of bank here.
Bob and Trudy are good friends and Alice is an employee working in a bank.
Bob asks Alice here, Alice, please send ten thousand dollar to Judy on my behalf.
Alice sends the money to Trudy.
Judy is mischievous and again replays the same message like, hey, Alice, please send Trudy ten thousand
dollars or else things like is the message from Bob again.
And Alice says, Bob, I've only sent and again sends the money to Trudy.
This is a replay attack.
Next is the denial of service attack.
It prevents normal use of communication facilities.
This attack may have a specific target, for example, and indeed all messages directed to a particular
destination.
Another form of service denial is the descriptions of an entire network with a very disabling the network
or overloading it by messages which degrade performance.
Let us consider the scenario of Alice and truly here to this intercept.
Bob is sending mixed signals.
Hello Alice.
How are you?
There truly is blocking the messages sent by Alice.
That send a message like, I'm fine, Bob, what's up?
But Bob is not receiving this message while I incents Alice, are you?
Therefore, this is an example of denial of service attack.
This can be very handy in case of browsers like if you're trying to access some website, but the website
is not replying to and you're just sitting idle waiting for the reply from Lipsett.
The website may have undergone the denial of service attack.
Now, we have discussed all types of passive and active attacks.
Let's go through the motives and goals in the attack, like to cause business loss information, to
create fear, to demean someone demanding ransom revenge, illegal access to organization, leaked confidential
information and promoting political beliefs.
Let us have a quick recap of what we learned in this lecture.
We learn different types of attacks like masquerade modification, replay denial of service.
In the next lecture, we will learn about the world's top security organizations.