Crypto Academy Season 3 | Advanced course : Let's Open The CryptoGraphy.

2개월 전

Hello All,

Welcome to Steemit Crypto Academy Season 3, My self @stream4u, I am from India, and one of your crypto professors. I welcome you all to my class.

Previously we learned about the Blockchain and understood how it works, in that same we have also seen how a block performs in a blockchain and then what happens when data gets changed in one of the blocks in Blockchain. In the last course, we also see how hashes work with Blockchain and their major roles. Hope the previous course and then summary on it was cleared to everyone.

One request, the way you engaged and commenting on Course posts, it will be good if you do the same on Summary posts also so that we will come to know that you understood about your submitted homework task, after all, Summary posts for you so that you can understand the overall about homework tasks and accordingly improve better in the next courses. We publish Summary Post every Monday.

Now let's start with our new course for this week. In this course, we will go more in deep and see about CryptoGraphy.


Before I explain CryptoGraphy let me give you one example first then you will understand it in a better way. You all know Warren Buffett, why he has not used a computer or email conversation?

In past, Warren Buffett has sent one private email to his friend but after sending that email the Government has tracked/cached that email and then go through it, the email contains a private message about one of the big Companies, in next few days that information which Warren Buffett has sent privately to his friend was published in the newspaper and then Warren Buffett was shocked, after that he never send the emails.

Now, what if there is a system through which you can send your message privately and only that person can read/receive it which who you want to send without any drop in the middle, here CryptoGraphy works for you.

What is CryptoGraphy & It's Techniques.

In technical terms, CryptoGraphy is the system that provides you a secure platform where you can communicate directly with the destination person in the presence of Third-Party services, and your communication will not drop, it will only remain in between the source and destination party.

In this process, the encryption and key method are used to transform input in the encrypted format then based on keys functionality the message can be decrypted. The pain text which humans can read changes into the computer language which we call as encryption then only that person can read it who has a required key, after using this key the message change from encrypt to decrypt which mean again into the plain text.

Key Points

  • Sensitivity - Data privately rotate in between and the destination, no one can understand this data.

  • Trustworthiness - The data cannot be alerted/modify.

  • Non Rejection - The sender can not deny once the data has been sent.

  • Validation - Sender and receiver can verify each other identification and the source/destination for the information.

Blockchain Key's CryptoGraphy.

Cryptocurrencies are built on key cryptography, this concept uses a Private key that you can not disclose with anyone and it is only with you which you need to secretly store, then a Public key which you can share with other people, also it helps for the identification.

Not only the Public key and the Private key, cryptocurrencies also use another concept that is Address which use to send/receive the fund, and in the same, you can also see the balance fund.

  • Public Key

It is one of the core parts of a blockchain that uses =d in multiple places to verify that the message is created into the Blockchain. Further, wallet creation and then sign the transaction which is depending on the Public chain. With the help of the public key, the public address gets generated by the hashing function. Public address similar to wallet address uses to send and receive the fund.

  • Private Key

The private key gives you full control over your waller and assets in it, only a private key can use to send assets to the destination address. The wallet generates the Private key for you and then while sending funds some software automatically signs that transaction with your private key.

Now, let's take an example to understand how and where Public, Private keys CryptoGraphy are used in transactions.

Person A wants to send x amount/message to Person B.

Person A first publishes his Public key which Person B knows. Then with the help of Private Key Person A sing the message/send assets while doing this the Digital Signature added to this particular transaction, the Digital signature confirms that Person A is a sender or message creator, after it is processed from the Person A. Person B on the other hand can use the Public Key of Person A to receive the message.

Digital Signature.

Just like we sign on the hard copy, document the Digital Signature is also quite same which process with the help of Private key. Digital Signature is a very critical part of CryptoGraphy.

The Digital signature confirms that the author who signs the transaction has an individual Private Key. Depending on the Private key, every transaction gets a different Digital Signature.

Digital Signature depending on the two functionality.

  • Sign - Transaction that we want to sign and the Private key, this help to produce is unique Digitale Signature to the Transaction.

Transaction -> Private Key -> Digital Signature

  • Verify - The Digital Signature and the Public Key produce the output based on whether the digital signature is authenticated or not.

Transaction -> Public Key -> Digital Signature

When a transaction is signed by the author the transaction goes into the pool which is further processed by the miners. As mentioned above the Public key can be shared, here miners authenticate the transaction with the Public key of the sender, once this has been verified they process a transaction in the next block and then the money/transaction send from one wallet to another wallet.

It is impossible to find a Private key from a Public key, similarly, it is impossible to find a Public key from a Private key.

Cryptocurrency Wallets CryptoGraphy.

Now let's see how Cryptocurrency Wallets CryptoGraphy works and the Public-Private key role in this. Let's take an example of the real world which is BANK to understand what the wallet is and how the Public-Private key relates to it.

Bank account number -> Crypto wallet address.

The Wallet address is similar to your Bank account number which you can share with anyone, then those who want to send you money can send it to your bank account number.

Crypto wallet address is similar to your Bank account, there will no issue if you share the Wallet address with others, actually it needs to share so that the other person can able to send you the assets.

The two cryptocurrency wallet addresses are never the same just like a bank account, which means no one can get your fund. But by Bank account, we can get the owner identification which is not the case in Cryptocurrency Wallets CryptoGraphy.

Example of Bitcoin address: 18LxzvGcJzSjDYJdYCHTe1G3i9ZGD26t9

We can see here the long length of the number, the combination of numbers ad characters, such an address can not be the same with another crypto wallet. Since Blockchain maintains transparency so that we can see how much fund this address has and how many transactions made yet, but as mentioned like BANK account we can not see the identification of the owner from the Crypto wallet address.

Password-> Private/Public Key.

Similar to the Bank account when you want to login into your account and send funds you will need to use your password, this password we can not share with anyone to make sure that funds are secure in the account.

The Private key is similar to your Bank account and this also cant be shared with anyone. The private key allows you to control your fund into the Crypto wallet and the same use to send the fund to other wallets. The private key is linked to the specific crypto wallet.

The public key is the mathematically generated number that gives an extra security layer to make sure it should not get hacked.

Private Key: 03ff350d29213775158a608b51e3eE898e507fe47f2d2e8c674de

Public Key: 90b1ebcfc12a11dfc5161abaa8169469fe1601d531

These are the examples of Public and Private key, it is not possible for a human to understand it but computer system can understand that it is linked to each other.

Another example like a credit or debit card, when we purchase something with the help of a credit or debit card we need to enter a PIN number which is security for credit or debit cards. When we entered and the transaction was made, the fund does not physically move from your account number to the store. This is what the similar is Cryptocurrency Wallets CryptoGraphy, with Private key you confirmed the transaction then you can use another wallet number to transfer the fund which is the only way to send crypto assets in two wallets.

Visual Demo to understand the functionality of Keys & Transaction CryptoGraphy.

To understand the background functionality of Keys CryptoGraphy we will be going to use a below Demo made by Anders Brownworth.

Blockchain Demo: Public-Private Keys and Signing

So there are 4 sections we have under this Demo that are Keys, Signature, Transaction, Blockchain. Here, we will be demonstrating 2 sections Keys and Signature. In Homework Task you will be explaining these 2 sections again as per your understanding and practical, also the rest of all sections will be under Homework Task on which you will be explained according to your researching and practice on this Demo.


In this section, we can see how the Public key is linked to the Private key and how the Public key generates which is linked to the Private key.

When I click on the Radom so it will provide me the random numbers for the Private and Public keys. When I tried to manually type Private key it will provide me a different Public key that linked to the custom Private key.

So I simply try to put value 1 as a Private key and it generated a Public key which is linked to the Private key. I can not share my Private key which is 1 but I can share my Public key.

Public Key: 0479be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798483ada7726a3c4655da4fbfc0e1108a8fd17b448a68554199c47d08ffb10d4b8

For humans is it difficult to know the Private key from this Public key but computer systems know that the Private Key 1 is linked to this Public key.


Note down that I put my private key as 1, now to get the signature value for my message/transaction, I will put some data as I enter "Steemit Crypto Academy" into the message.

What we see here, the Private key is needed to process the transaction/message, and by singing it generates and provides Digital Signature to my message/transaction.

As mentioned above in the Sign section we can see here that, Transaction -> Private Key -> Digital Signature

Let's verify this transaction now, check the above public key.

Here, I used the Public key of the sender and the Digital signature for the message. Everything is valid, clicking on Verify the transaction will get verified.

As seen above in the verify section, Transaction -> Public Key -> Digital Signature.

Merkle Tree CryptoGraphy.

While checking the transaction in Blockchain Explorer did you see Merkle root in the details, check below.


To understand Merkle Root and Merkle Tree let's first understand what was the problem in the Blockchain that Merkle Tree solved.

The Blockchain is made with a thousand of Blocks, each Block has thousands of transactions and each transaction has a unique ID, here you can imagine how much memory and computing power gets utilized.

The solution is Merkle Tree which provides us the details about all transactions in a block. With the help of Merkle Tree, we can use only small data as needed while processing and verification of any transaction. It reduces computing power, memory, and also provides higher security.

How It Works?

The Merkle Tree records all transactions in a block. The Merkle Tree continually calculates the hashing till the last one left which call as Merkle Root. In the above diagram, the top block is known as Merkle Root. The Merkle Root can be read from bottom to top.

The node has a hash of transaction data and the non-node has the same previous hash like if it is an odd number of Block then the last hash will be duplicate.

In the above diagram A, B, C, D are the transaction with their Hash value 1,2,3,4. The first two blocks' hash values will give results 1,2 and similarly, the next two blocks give results 3,4, then again hashed to generate the last hash which is 1234 that known as Merkle Root.

In this way, the Merkle Tee reduces the time, disk size, power and helps to find the specific transaction quickly.

Homework Task.

Hope you liked this course as we see the inside view of CryptoGraphy, here we learned how CryptoGraphy works in Cryptocurrencies with their Keys, wallets, and transactions.

While making a Homework Task kindly make sure that this is the Advance Level course hence before start to work on this Homework Task, I will request first to understand the questions and accordingly work on it, research more, study, and understand it first then prepare a task with the details and own words.

You also need to focus on a presentation while working on a Homework Task, make sure you submit the homework task with a good presentation, try to use markdowns to highlight the important note in your task.

The title for the Homework Task will be in the format, Crypto Academy / Season 3 / Week 8 - Homework Post for [@stream4u] - Let's Open The CryptoGraphy.

Below are the questions which you need to explain through your Homework Task.

  1. Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms (Few names of the Blockchain Platforms)?
  2. Explain the Public Key CryptoGraphy.
  3. Explain the Private Key CryptoGraphy.
  4. Explain the Digital Signatures CryptoGraphy and what is Singing Of Transaction/Message?
  5. Explain what is Symmetric and Asymmetric cryptography?
  6. How Blockchain Wallets CryptoGraphy works and explains the available types of Crypto Wallets.
  7. What is the Merkle trees and What its importance in blockchain?
  8. Practical + Theory, do some practical research, study on Blockchain Demo: Public / Private Keys & Signing and then explain the functionality of Key, Signature, Transaction, Blockchain with proper screenshots of yours practical. (Do study well for this topic)
    9 Conclusion. (The overall understanding of CryptoGraphy)

Homework Guidelines.

  • Make sure you submit your Homework Task in the Steemit Crypto Academy community.

  • Users having a reputation of 60 or above, and having a minimum SP of 500(excluding any delegated-in SP) are eligible to partake in this Task.

  • All information contained in a Homework Task should be your own as plagiarism will not be tolerated.

  • Use images from copyright-free sources.

  • Add tag #stream4u-s3week8 & #cryptoacademy in your Homework Task and should be in the first two tags. Tag correctly otherwise the Task will not get visited in a sequence and on time.

  • Add me as @stream4u somewhere in your Homework Task.

  • This homework task will run from 16 August 2021 To 21 August 2021 Till Time- 11:59 PM UTC, make sure to submit before the time ends.

For any concerns, doubts, questions on homework tasks, you can ask me in the comment section below before making Task.

Thank You.
Crypto Professors : Steemit Crypto Academy

Authors get paid when people like you upvote their post.
If you enjoyed what you read here, create your account today and start earning FREE STEEM!
Sort Order:  trending

Hi @jamezmccoy, @rosanita, @opeyemioguns, @adriancabrera, @huzaifanaveed1

mention few names which are the Blockchain Platforms?

First, let me answer you that this means you simply need to mention the names of the blockchain platforms.

Now you all please help me here as the same question asked from you all. I am just asking as a friendly nature because I wanted to understand it. I really don't understand where this question is confusing and how it relates to or connecting to the warren buffet, there is no any relation between Blockchain Platform and Warren Buffet.

Not sure but we might read the post in a different language(translator) which could be the reason the output of the question getting different.

I try to edit the question to give more clarity on it. But really did not understand what to edit because the question is much clear mention few names which are the Blockchain Platforms.

Please help me to understand how or where you get confused about this question so that it will help me to modify the question to give more clarity so that you and others will not get confused. Also, it will help me in the future to try to give clarity.

Waiting for your responses.

Thank You.



It's cleared now. I just submitted my assignment. here it is.


Hello professor, I was also waiting for this answer from you, to the clarification of question number 1. I think that when translating into Spanish it is confusing, because it should say in Spanish only: Mention some blockchain platforms.

As it is written it seems that it refers to something else about the blockchain and not just their names.

Thank you very much for your attention, I am working on this task.

#venezuela #affable


Thank you professor for taking out time and engaging with the us. It creates a healthy bond, I believe.

When I read that question I was confused as as I thought something was missing from this question or like you wanted to ask something else. I thought maybe there's a word missing as you are a human too professor and it is very much possible to have this humanly error. So that is why I asked it as this is an advanced level course and it takes lot of time for me to write your assignment, answering every detail asked by you, so I didn't want to take any risk. If I hadn't understood and written down the assignment without clarification from you, there was a huge possibility of losing a single or two marks which I don't want to. This is the last week and I want to put my extra 100% efforts

Thank you once again professor @stream4u for your clarification. It honestly meant alot that you wanted input from your students too. I'll be submitting my assignment very soon.


Its been clarified professor thanks


Hola profesor gracias por aclarar mi duda.


Professor I've a confusion what do you mean by

mention few names which are the Blockchain Platforms?


Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms?

It means the names of blockchain platforms.

buenas tardes profesor @stream4u saludos, con respecto a la primera pregunta no lo tengo claro, por favor si puede ser mas especifico ya que tenia dudas y con su respuesta al amigo @jamezmccoy mas confundido quede.





This is Not a Big issue but actually, you can check here, @jamezmccoy has edited his initial comment after my comment and you know we did not get a notification for the edited comment hence I did not get a chance to re-visit his edited comment if he could simply reply on my comment and asked the same then I may reply him on time but still as I said this not a big issue.

Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms?

mention a few names which are the Blockchain Platforms. This means you simply need to mention the names of the blockchain platforms.


Mil gracias Profesor @stream4u ya entiendo!!


All has been made clear sir

I want to participate in this contest but my reputation score is 37 only. I have steep enough power i.e. 528 SP. Can I participate in this course?

I am old user of Steemit join in 2017. But due to my family health problem, I was not active on Steemit. So, please allow me to participate in this course.

Regards @printskill


The requirement to participate in this course is a minimum reputation of 60 and at least 500 Steem Power of their own (not delegated to them).

Please check The Steemit Crypto Academy Weekly Update [ August 16th, 2021 ] : New Courses

To participate in the Advanced courses students will need to have a minimum reputation of 60 and at least 500 Steem Power of their own (not delegated to them).

Thank You.
Crypto Professors : Steemit Crypto Academy



Ok, I can understand. Thank you for your quick reply.

Thanks for the lectures prof.

Hello professor, the number one question isn't still clear and that's why I'm still unable to submit my assistant, did you mean

Do you mean names of of blockchain platforms or names of individuals affected like warren buffet ??


Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms?

It means the names of of blockchain platforms.

That's very great Lecturing prof. Thanks for the updates. I would definitely try my hand on this.

Hello professor. Here is my assignment. Thank you for this wonderful course

Hello prof. In the lesson, you mention that

we will be demonstrating 2 sections Keys and Signature, the rest of the two will be under Homework Task which you will be explained by researching and practice on this Demo.

But in the homework task, it is mention to explain all 4 with screenshots. So we have to demonstrate all four or only Transaction and Blockchain?


Yes, good observation, and thank you for notifying me. My bad.

While writing a course I feel I should give some sections to you all for practice so that you can check practically everything and come up with your details so I mentioned like that. But at the time of the homework question, I feel even I mentioned few sections, let you also do the same and see how it works and then come with your details so in question I gave all section.

Thank you, I have changed my statement now.


Thanks for the clarification prof.!



professor, i'm is confused about question no1, do you mean feature or future. I don't understand the use of the word feature, (How You Would Like To See Cryptocurrency In The Future?, what feature does you mean prof?)

Buenas tardes profesor @stream4u, muchas gracias por su clase de esta semana. Adjunto mi tarea espero sea de su agrado.

Crypto Academy | Season 3 - Week 8 | Homework Post for professor @stream4u | Let's Open The CryptoGraphy | By @minikay

Is my pleasure to do your asignment once again my professor @stream4u here is home work link Link

Hello Professor @stream4u,
This is My Entry to homework post.
Thank you.

Explicit lecture sir.. Will be sure to participate... In

mention few names which are the Blockchain Platforms?

Do you mean names of of blockchain platforms or names of individuals affected like warren buffet ??



Profesor a que se refiere con nombres tengo la duda tambien.



Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms?

It means the names of blockchain platforms.


same question on my mind


Explain the Blockchain CryptoGraphy and mention few names which are the Blockchain Platforms?

It means the names of blockchain platforms.


It means the names of blockchain platforms.

Halo good professor, I submitted my post ahead of time today. It was three hours ago. Kindly look at it sir @stream4u, thank you.
Link is Crypto Academy Season 3 Week 8: Homework Post for @stream4u: Let's Open The Blockchain; Cryptography

Greetings professor i hope you will be well. I am here with my homework about the Blockchain Cryptography.

Crypto Academy / Season 3 / Week 8 - Homework Post for @stream4u / Blockchain CryptoGraphy / Symmetric and Asymmetric Cryptography

Please check it when you are available and sorry for the inconvenience.

this is another interesting lesson and I will submit my participation soon. Thanks for bringing this learningful lesson.

¡Hola profe, un placer participar en su tarea de esta última semana! Espero se encuentre bien, por aquí le adjunto mi tarea.


¡Espero disfrute sus vacaciones! un saludo.

Hello sir, I have submitted my homework post for your kind consideration. But it is not showing on the relevant tag page. So, I am sending you link of my post. Here is the link.

Thanks for the great lecture Professor @stream4u. Here is my homework.

Hello professor @stream4u
This is my homework post for your lesson.
Thank you

Thank you so much Professor @stream4u for the teaching. It added a whole lot to me.

Below is the link to my homework.

Respected Professor @stream4u, I have already sent my link because my post has been skipped due to some problem. Plz review my post as it is 2 days old post now. Thanks


what was the problem?


It was edited and it is showing on the page very below as it is not showing at the number it should have been.


You can see, sir, that my post is showing with 4 days old post while my post is 2 days old and it is not at proper place. That's why it has been skipped.


I was writing the post and it was posted by mistake while it was incomplete at that time. Then I deleted that post and reposted it after completion.


Thank you, it will get verified shortly.


It has been verified now, but I will suggest you take care of such things in the future because such activity looks suspicious.


It happened by mistake. But I will take care of it in future. Thanks for review, Sir