H 530: Blockchains (15 pts)

What you need

Purpose

To practice using a simple demonstration blockchain.

Live Blockchain

In a Web browser, go to

https://andersbrownworth.com/blockchain/blockchain

The demo appears, as shown below.

At first, there is no data stored in the blocks, and all the blocks are valid, with green backgrounds.

Enter some data in the first block. The background turns red, as shown below, indicating that all the blocks are now invalid.

In block #1, click the Mine button. The Nonce changes as required to make the Hash start with four zeroes, and the background turns green, indicating that this block is now valid. as shown below.

Mining a Blockchain

Put this data in the blockchain, as shown below.

Mine the blocks, as shown below.

Enter into the form below to record your success.

H 530.1: Nonce for Block #3 (5 pts)

Find the correct nonce for block #3, which is govered by a green rectangle in the image above.

That's the flag.


Challenge X7.2: Coinbase (10 pts.)

In the Blockchain Demo page, at the top right, click the Coinbase tab.

Now the blocks include rewards for mining, which come from the Coinbase, and structured transaction data, as shown below.

Make these changes in the data, as shown below.

Mine the blocks, as shown below.

H 530.1: Nonce for Block #5 (10 pts)

Find the correct nonce for block #5, which is govered by a green rectangle in the image above.

That's the flag.

Posted 6-6-18 by Sam Bowne
Renumbered and updated 6-9-2020