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helloharshmishra004
  • 8/9/2024

Category

📚
Learning
Transcript
00:00So, for those who are new and don't know how to choose a domain,
00:07or who don't even have a basic knowledge of what to do and what fields are there,
00:12I would like to tell you that there is a portal for Insidern.
00:15You can find the link of Insidern everywhere.
00:17So, this is the portal where you can see that there are a lot of courses.
00:21You can go to courses and enroll your course here.
00:25When you click on courses, you will find two courses.
00:28You can enroll here.
00:29This is my course. It is free of cost for now.
00:32So, when you come here, you will get all the things here.
00:36And if you want to see, there is an assignment uploaded here.
00:39Do attend your previous orientation.
00:43I mean, do it later. You have to do networking now.
00:46Rest, the live session of orientation is also included here.
00:49I took 2 hours.
00:50Rest, I uploaded a project as well.
00:53How to do projects, all those things.
00:56Then you can see the lectures of networking here.
00:58All the lectures are there.
00:59Week 1 and week 2, all are uploaded in many parts.
01:03All are lectures of 40-45 minutes, 1-1 hours.
01:06So, I have already told you in a very deep way,
01:09the lectures in my portals, you can go and see here.
01:12But if you have any more doubts,
01:14I mean, what should be done and what should not be done,
01:16If anyone has any doubt, I think someone has raised it.
01:20So, if anyone has any particular doubt,
01:24I mean, if there is a doubt in the lectures,
01:26I mean, the one-shot video that I am going to take today,
01:28that will be at a good level.
01:30I mean, you understand that 90% of the topics will be covered very well.
01:34But the thing about lectures is different.
01:37That is, 7-hour thing and 19-hour thing.
01:39There will be some difference between the two.
01:41So, one-shot is for those who have not started anything in this field yet.
01:44I mean, when they start,
01:46they will get a good help in the starting.
01:49So, they can continue their journey ahead.
01:52But for those who have not done, let me tell you.
01:54Week 1 and Week 2, many lectures have been uploaded here in Cyber.
01:58I mean, those who have seen,
02:00you will see in the courses,
02:02in Fundamentals of Hacking.
02:04So, you can see here in Week 1 and Week 2,
02:06all the lectures are uploaded.
02:08So, you come here and see your lectures.
02:10If for deep understanding,
02:12after today's lecture, all the lectures will be easy for you.
02:14Let me tell you first.
02:15It will be easy for you.
02:16And if you have any doubt,
02:18you can message me.
02:20That there is a doubt in this particular field.
02:22And for orientation,
02:24which domain you should choose,
02:26you can watch my orientation live session video once.
02:28Around 2 hours.
02:30So, you will get a very good detailed idea.
02:32What are the fields in which you can earn money.
02:34Because the main motive is money.
02:36So, you can see according to you.
02:38So, before starting the lecture,
02:40my main thing today was that
02:42before starting the lecture,
02:44I had sent you a lot of hacking books.
02:46I mean, you see this hacking book, see that.
02:48So, let me tell you a little bit.
02:50I have a lot of resources,
02:52but you want to go to such a high level.
02:54Because I will take you to what level,
02:56I want to show you a little bit.
02:58So that you can get an idea
03:00to what level I am teaching you
03:02these particular languages,
03:04what I want to do.
03:06So, this is a book.
03:08I mean, this is a book.
03:10You have read a lot of books.
03:12Whether you read or not, it is up to you.
03:14But what am I going to make you do?
03:16So, I want to give you an idea today.
03:18This particular book is of Embedded Systems.
03:20C, C++ language, which I tell you to read well.
03:22Do all these things well.
03:24Do the hardware well.
03:26So, why do I say this, I will show you.
03:28You must have read a lot of languages well,
03:30but you have not understood this diagram yet.
03:32When you read the operating system,
03:34you will understand all these diagrams.
03:36You will understand a lot of things.
03:38So, you know what my main motive is to get you to do.
03:40Which I am doing myself.
03:42I tell them the main motive.
03:44We are not going to use any tools in hacking.
03:46I mean, the tools that people say,
03:48no, we don't use tools.
03:50We will build our own operating system.
03:52We should have our own operating system.
03:54We should have our own coding language.
03:56Think about the level.
03:58You don't have to patent your own coding language,
04:00your own operating system,
04:02because you have kept it for your personal use.
04:04The operating system is your own,
04:06the coding language is your own,
04:08and you don't have to make the GUI on it,
04:10because you don't have to sell it to anyone.
04:12I will teach you how to do all these things myself.
04:14You will reach such a level.
04:16You should know how to make tools yourself.
04:18You should know how to make everything yourself.
04:20You will not get what you are thinking by using.
04:22If you get money by using tools,
04:24then all the teachers,
04:26they have a good car,
04:28they have a rich life.
04:30But they have their own detailed knowledge.
04:32So, if you want to get detailed knowledge,
04:34then select all domain.
04:36In that,
04:38how to make OS operating system,
04:40my next topic will be on operating system.
04:42Security of operating system,
04:44its fundamentals,
04:46its architecture,
04:48many things will come.
04:50So, I have shown you an idea.
04:52We will talk about embedded system,
04:54neural networking,
04:56how to make Metasploit,
04:58there are many languages,
05:00many things,
05:02many things to do.
05:04But there is only one thing for this,
05:06you will have to sit for 16-17 hours.
05:08There are many languages,
05:10which you have heard for the first time.
05:12So, I have a lot of resources.
05:14And you will think,
05:16this is only my first folder.
05:18I have 3-4 folders.
05:20So, you understand,
05:22resources are complete,
05:24you just have to sit and start working.
05:26So, this will be a very good resources platform.
05:28If you think you need resources,
05:30then you can tell me,
05:32I will send you.
05:34But I don't think so,
05:36because I haven't started yet.
05:38The day you start networking,
05:40after that, you will start understanding things.
05:42So, those people,
05:44who can't attend our 6 hours,
05:46then you can go and see Lexis.
05:48Lexis is already uploaded.
05:50This is for those people,
05:52who want to understand,
05:54that yes, we haven't started yet,
05:56and if we have a session with a teacher,
05:58then it will be easy.
06:00So, this is for those people.
06:02And if someone wants to increase their concepts,
06:04then this is a good app for that.
06:06So, I think it's a good introduction.
06:08Let's start networking.
06:10Before starting networking,
06:12I would like to tell you,
06:14that the fundamentals you have to cover,
06:16first, whether you are in software,
06:18web or anything else,
06:20your first step is networking.
06:22The first thing you have to cover is networking.
06:24What do you have to understand?
06:26How does networking work?
06:28Why is networking important?
06:30Any tool, maximum tools work on networking concepts.
06:32Your web works on networking concepts.
06:34If you do pen testing,
06:36then you can't do it without networking.
06:38If you do bug bounting,
06:40then you can't do it without web.
06:42You have to know about networking for web.
06:44So, you can say,
06:46that the first step in life,
06:48is networking.
06:50If we see,
06:52the achievement section of hacking,
06:54then the first step starts with networking.
06:56Without networking,
06:58you can't do anything.
07:00So, let's start networking.
07:02Let me tell you,
07:04I have covered everything in the lectures.
07:06I have covered up to DNS.
07:08I haven't completed DNS yet.
07:10Today, I will tell you,
07:12what all topics I will cover in 6 hours.
07:16In 6 hours,
07:18the last topic will be,
07:20FTP, UDP and TCP.
07:22I will introduce you,
07:24to all the topics.
07:26I have covered more than 50 topics,
07:28but more than 100 topics.
07:30I have written 50 topics,
07:32that I will cover 50 topics.
07:34But, it's not about only 50 topics.
07:36It's about more than 100 topics,
07:38that I will cover today.
07:40So, be prepared.
07:42So, let's start.
07:54So, let's start networking.
07:56I can teach in two ways.
07:58Either through PPT,
08:00or through notes.
08:02So, these are my notes.
08:04I have provided it in the group.
08:06By teaching through notes,
08:08I can show you many things in detail.
08:10I can show you many things in detail.
08:12I can show you many things in detail.
08:14If I want to make a slide,
08:16it will take more than 200-300 pages.
08:18I have to send you 1-2 GB to send it.
08:20It's better than that.
08:22It's better to continue with this.
08:24So, let's start networking.
08:26It's been 8-10 minutes.
08:28Most of you must have joined.
08:30People will join later.
08:32So, let's talk about networking.
08:34Before starting networking,
08:36let me tell you,
08:38when there were no computers,
08:40people used to think,
08:42how to talk to each other.
08:44Let's say, there are two people.
08:46Let's say, there are two people.
08:48There is no concept of networking.
08:50There is no concept of networking.
08:52There is no concept of networking.
08:54If people have to send a PDF file,
08:56how do they send it?
08:58First, wear a shoe.
09:00Take out a pen drive.
09:02Put the file in the pen drive.
09:04Put it in the USB.
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23:48There was no other step.
23:50There was no other step.
23:52There was no other step.
23:54There was no other step.
23:56There was no other step.
23:58There was no other step.
24:00There was no other step.
24:02There was no other step.
24:04There was no other step.
24:06There was no other step.
24:08There was no other step.
24:10There was no other step.
24:12There was no other step.
24:14There was no other step.
24:16There was no other step.
24:18There was no other step.
24:20There was no other step.
24:22There was no other step.
24:24There was no other step.
24:26There was no other step.
24:28There was no other step.
24:30There was no other step.
24:32There was no other step.
24:34There was no other step.
24:36There was no other step.
24:38There was no other step.
24:40There was no other step.
24:42There was no other step.
24:44There was no other step.
24:46There was no other step.
24:48There was no other step.
24:50There was no other step.
24:52There was no other step.
24:54There was no other step.
24:56There was no other step.
24:58There was no other step.
25:00There was no other step.
25:02There was no other step.
25:04There was no other step.
25:06There was no other step.
25:08There was no other step.
25:10There was no other step.
25:12There was no other step.
25:14There was no other step.
25:16There was no other step.
25:18There was no other step.
25:20There was no other step.
25:22There was no other step.
25:24There was no other step.
25:26There was no other step.
25:28There was no other step.
25:30There was no other step.
25:32There was no other step.
25:34There was no other step.
25:36There was no other step.
25:38There was no other step.
25:40There should be some detail in this particular packaging.
25:42Which computer should go and which computer should not go.
25:44Which computer should go and which computer should not go.
25:46NIC will tell all these things.
25:48That's why I said without NIC,
25:50your computer can't talk.
25:52It can't connect to any network.
25:54Because NIC is responsible for sending the packets of your computer.
25:56Do you understand?
25:58Any particular doubt?
26:00Any particular doubt?
26:04If there is, then tell me.
26:06If you have any doubt for 5 minutes,
26:08I will clear your doubts.
26:10That's why I was doing a live session.
26:12Any doubt?
26:14Can you continue?
26:16Give me a thumbs up.
26:18Okay, no problem.
26:20So,
26:22You got an idea that
26:24any computer is sending a message through NIC,
26:26so it will send through a packet.
26:28Like, my canister is a packet,
26:30in which I will put a message,
26:32and the message will go to the packet.
26:34Now,
26:36So, when you are thinking about what information you want to put in the packet,
26:40For example, let me give you an address from Flipkart.
26:50You have a partial of Flipkart.
26:52Your name, your address, your city, your mobile number, your PIN code.
26:56All these things are noticed in this.
26:57So that it gets to know what is delivering your message.
27:00For example, what is delivering your message here? It is herping.
27:06Yes, you can continue. You can ask if there is any doubt.
27:12Hello.
27:13If you have any doubt, you can ask in the chat or anywhere.
27:16You can also ask by turning on the mic.
27:22I think so.
27:23You can message me.
27:25If I stop the session again and again, the rest of the students will get the same fault.
27:29So, at the end, when I complete this particular half, I will pick up your doubt.
27:34Write to me in the message.
27:37I will clear you there.
27:40So, the packet that is sending you here, the delivery boy is herb.
27:44Why?
27:46What will herb do?
27:47Whatever message is coming from here, it will send it to the other computer.
27:49This is your sender computer and one receiver computer.
27:53Now, the herb that is sending, it should know that the packet that is coming to it should have an address.
27:59There should be a PIN code.
28:00There should be a mobile number.
28:01Except there should be things, but there is no mobile number on the networking or computer.
28:05So, what are the things that are written?
28:07Now I will tell you.
28:08This is the NIC that is packing the packet.
28:11Which is putting the message in the packet.
28:13This is the packet that is called the canister.
28:15Whatever things are put in this canister, what information does it put in it and send it to herbs?
28:20I will tell you that.
28:21The first is the MAC address of the receptionist.
28:23The MAC address of the sender.
28:24Data and CRC.
28:27Okay.
28:28Now what are all these things?
28:30First of all, you will have to understand this.
28:32Let's create a little doubt in your mind.
28:35So that you can understand easily.
28:37Create doubt so that when I explain, you can understand easily.
28:40Assume you know your friend.
28:43Okay.
28:44You are talking to your friend and you have sent him a particular parcel.
28:48You know his address.
28:50You know his mobile number.
28:51He will easily deliver it.
28:53But for example, you are sending your parcel to a computer or a friend.
28:58If you don't know his address, how will you send him a parcel?
29:01For example, this computer wants to send a message to another computer through herbs.
29:07He wants to send a parcel.
29:09He doesn't know his MAC address.
29:12Because computers don't know each other's MAC address.
29:15So he doesn't know the MAC address.
29:17The information he wrote here, the MAC address of the sender.
29:20Sorry, the MAC address of the receptionist.
29:22How will he know this MAC address?
29:24Tell me.
29:26How will he know what his MAC address is?
29:31Any idea?
29:32Anyone?
29:33Brother, I don't know anyone.
29:35I don't know any computer.
29:36Another computer.
29:37So how will he know that MAC address?
29:39Because it will send a request.
29:41Okay, nice.
29:42Someone has read the lecture.
29:44Okay.
29:45So how does the computer know the MAC address of the receptionist?
29:49Now it is a little ahead.
29:51It wasn't included in the lecture.
29:52I mean, it wasn't included in the lecture I gave.
29:54A broadcast will be sent.
29:56Yes, a broadcast will be sent.
29:58What will this computer do?
30:00This computer, which is sending packets.
30:03This whole, for example, a lot of computers are connected to this particular herb.
30:08Okay.
30:09A lot of computers are connected to this particular herb.
30:12Now this computer will send a broadcast message.
30:16What will it send?
30:17A broadcast message.
30:18What is a broadcast message?
30:20Brother, I don't know anyone.
30:23What?
30:24I don't know the MAC address of any computer.
30:26You guys send me your MAC address.
30:28Okay.
30:29You guys send me your MAC address.
30:31Okay.
30:32Generally, to remove this thing.
30:35To remove this particular thing.
30:38Terms of a routing table came.
30:40If you don't have an idea, listen to the routing table.
30:42So many people will be there.
30:43What is a routing table?
30:44But those who have no idea.
30:46I will tell you later.
30:47What do herbs do?
30:48They make a routing table with a tab.
30:50Okay.
30:51What do herbs do?
30:52They make a routing table with a tab.
30:54What will it do?
30:55A broadcast message will send a PC to another PC.
30:57So the particular broadcast message.
30:59For example, I sent a computer.
31:01Brother, tell me your MAC address.
31:03I have to send you this packet.
31:05Now it depends on this computer.
31:06Will he give his MAC address to him or not?
31:09Okay.
31:10It is possible that the computer does not give him the MAC address.
31:12Okay.
31:13Now I want to give you a good example.
31:15Because you have to listen to it in detail.
31:17Assume that at least 20 computers are connected to this particular hub.
31:23I will not be able to draw 20.
31:25But I will tell you as much as I can draw.
31:27Assume that the message sent by this particular hub.
31:3020 computers are connected to this particular hub.
31:32Okay.
31:33And 20 computers have to send a message to other computers at the same time.
31:38Okay.
31:3920 computers have to send different messages to 20 different computers.
31:43Don't you think it will be less hectic?
31:45Send broadcast messages to everyone first.
31:47Don't you think it will be less hectic?
31:48Send broadcast messages to everyone first.
31:50How many messages will you see at a time?
31:53Even the hubs will feel that only one particular message will be seen at a time.
31:56How much will the hub be able to see?
31:57Assume that this is a network of 100 computers and not 20.
31:59Then?
32:00Not all things will happen at the same time.
32:02So what happens?
32:03What do these hubs generally do?
32:04Like a computer is connected to it.
32:06People used to note down its MAC address.
32:08And the particular note down where it is done is called a table.
32:11Now call it a routing table.
32:12Routing table means the table of the router.
32:14When I teach the router, the router table will come in it.
32:16Now let's say I give it another name.
32:18I give it a hub table.
32:20What will happen?
32:21A hub table will be made.
32:22Let me tell you through an example.
32:24Make a hub table.
32:25Like a computer will connect to this particular hub.
32:27What will happen to it?
32:28It will take its MAC address.
32:29And it will note it down in its table.
32:31For example, this is the first computer.
32:32This is the second.
32:33By doing this, 20 computers have taken all the information.
32:36Okay.
32:37Now, if no one sends a message again and again,
32:39then what will happen?
32:42This particular computer already has the MAC address of all the computers.
32:45This particular computer has to send a message.
32:47For example, the first computer has to send a message to the fourth computer through the hub.
32:52This is the fourth computer.
32:53And this is the first computer.
32:54So, it has to send a message to the fourth computer.
32:56Okay.
32:57Now, it will send a message to the fourth computer.
32:59So, we have an idea of how it will send a message to the first and fourth computers.
33:02You are understanding this.
33:03So, one concept is to broadcast.
33:07Broadcast means sending a whole packet to the entire network.
33:10All the computers that are connected, send a packet to everyone.
33:12In which it is written that I do not know your MAC address.
33:15You tell me your MAC address.
33:16Or if this is a very large network,
33:19then it is possible that the hub has a hub table in which all the computers have MAC addresses.
33:23So, what will it do?
33:24It will send a request to the hub.
33:25That you tell me the MAC address of the fourth computer.
33:27So, the hub will tell it the MAC address of the fourth computer.
33:30Simple process.
33:31Do you understand?
33:33What type is this?
33:37Do you understand?
33:38Broadcast.
33:40What can be broadcast?
33:42Okay.
33:43So, it is possible that the computer has made a hub table in which all the MAC addresses are written.
33:50It will send it through that MAC address.
33:52Okay.
33:53So, the computer knows the MAC address of the center.
33:56After that, the data will come.
33:57What will happen in the data?
33:58Whatever it sends.
33:59Now, after that comes a CRC.
34:01Cyclic Residences Check.
34:04What is this CRC?
34:05You can read it.
34:06Cyclic Residences Check.
34:07Which is called CRC number.
34:09What is this CRC number?
34:11Okay.
34:12Now, let's talk about this CRC number in a little detail.
34:15One computer.
34:17Now, I will also tell you a little bit about the flaw of the network.
34:19From where you will also know a little bit about the techniques of hacking.
34:23One is my hub.
34:24My computer.
34:25Another computer.
34:26Okay.
34:29Okay.
34:30Identification number.
34:31Okay.
34:32You can't say identification number.
34:34But yes, it is included for security purposes.
34:37Okay.
34:38So, what is CRC?
34:39Cyclic Residences.
34:40Cycle.
34:41Which is called.
34:42Now, what will it do?
34:44My computer is number one.
34:45Computer number four.
34:46And this is computer number three.
34:47Okay.
34:49Whenever this particular NIC sends a packet.
34:51In which the CRC number is also included.
34:53Now, these packets.
34:55These packets are received by all computers.
34:59What is the mistake of hubs?
35:01I will tell you.
35:02Hubs or Ethernet or anything.
35:04I am not talking about routers.
35:06Hubs or internet.
35:07Whoever will use the concept of MAC address.
35:10MAC address.
35:11I will repeat it before.
35:12Whoever is sending packets with the concept of MAC address.
35:15In this, did you read the IP address anywhere?
35:16Is the IP address included?
35:17No.
35:18What is included here?
35:19MAC address.
35:20Whatever thing will send packets through MAC address.
35:23It will generally be a LAN network.
35:25Whatever packets are going to that LAN network.
35:27They will be included in all computers.
35:30Which is connected to that particular network.
35:33If 20 computers are connected to this hub.
35:35Then this particular first computer.
35:37Which will send a message.
35:38It will be received by 20 computers.
35:41If it is received by 20 computers.
35:43Then you feel that this is a security issue.
35:45That means security can end here.
35:48That means I have sent a good hidden data file to someone.
35:51And read all the computers.
35:53So this thing should not happen.
35:54For this, a CRC number came.
35:57What is this CRC number?
35:58I will tell you.
35:59The type of data you have.
36:01That data.
36:02This is a division algorithm method.
36:05What?
36:06This is a division algorithm method.
36:08They convert this.
36:10And make a particular key.
36:12Or a number comes.
36:14They have a number.
36:16That number is generally called CRC.
36:18Or a key.
36:19Okay.
36:20We will call it a CRC number.
36:21Otherwise, we will call it a key.
36:23Now this CRC number.
36:25Such keys are there.
36:27For example.
36:28You have a lock.
36:29Okay.
36:31And what have you done?
36:32You have locked the house.
36:33And you have given this particular type of lock.
36:35To one of your neighbors.
36:37You have given it to your neighbor.
36:38If you have any problem.
36:39If you have a problem here in our house.
36:40Then you can open the lock and check.
36:42Okay.
36:43This type of keys.
36:44The type of keys of CRC.
36:46It is spread throughout the network.
36:49Okay.
36:50But.
36:51There is one thing in this.
36:52What happens?
36:53For example.
36:54This is my computer.
36:56I sent a message through Herbs.
37:00I sent a message through Herbs.
37:02So when I put the MAC address of the receptionist and the sender in it.
37:06Still Herbs is sending all the computers.
37:08But Herbs does one more thing with it.
37:10What does it do?
37:11The receptionist.
37:12Means who has to go.
37:14Whoever has to go.
37:15With that particular MAC address.
37:17It sends a particular key.
37:19What does it do?
37:20It sends a particular key.
37:21Which this particular computer gives to Herbs.
37:23This key.
37:24This Herbs does not give to everyone.
37:26Yes.
37:27Packet provides to everyone.
37:28But this key.
37:29It only goes to the one.
37:30Whose receptionist MAC address is written.
37:32It should go.
37:33So this is the key of the CRC.
37:36It will be received by the same computer.
37:37Whose MAC address is written here.
37:39Like it was written on the fourth.
37:40First sent the fourth.
37:42Now what will it do?
37:43With this key.
37:44This particular packet.
37:45You can open it and check.
37:47And who will have this key?
37:48Only the fourth will have it.
37:50No other computer will have it.
37:51Assume that I have received the first second.
37:52The second does not have the key.
37:53To open this packet.
37:56This is the CRC number.
37:58What is the CRC?
38:00What is the CRC?
38:04Are you clear about the CRC?
38:08Okay.
38:09Let's go.
38:10Let's start.
38:11When will you be clear about the CRC?
38:12What is the CRC?
38:14So receptionist.
38:17CRC one more time please.
38:19Okay.
38:21No problem.
38:23So this was our receptionist.
38:25Senders, data and CRC number.
38:27These three topics.
38:29In this I was telling.
38:31In the packet.
38:32Like we have address.
38:33Phone number.
38:34All these things are there.
38:35What happens?
38:36MAC address of the receptionist.
38:37Senders data and CRC number.
38:39Okay.
38:40You can see.