Please help me understand encrypted information about Blockchain

[chegmarco]

Hello.

I would like to know how to recognize on the Blockchain website the following informations:

1 - SHA2 hashes of the plaintext ?
2 - Base64 Encoding of Signatures ?

In fact, I'm studying Blockchain and how it works. So help me to understand by giving me if it is possible by CAPTURE OF SCREEN how to recognize this information (SHA2 hashes of the plaintext and Signatures encoded in base64) on the website of the Blockchain.

Thank you in advance.

[achow101]

First of all, there is no "the website of the blockchain". The blockchain does not have a website nor is there any official website for exploring it. There are many blockchain explorers each of which can give you a slightly different view of the same information.

Secondly, nothing is encrypted in the Bitcoin blockchain. There aren't "SHA2 hashes of the plaintext". There aren't "base64 encodings of signatures". Signatures aren't encoded in base64 and nothing is encrypted in Bitcoin.

Blockchain explorers will typically show you the transaction id for all transactions. This transaction id is the double SHA256 of the transaction. Perhaps that is the "SHA2 of the plaintext" that you are referring to?

Signatures are encoded using DER encoding and their byte values are just written directly to a transaction, it is not encoded in base64. You will find signatures in most transaction inputs, but signatures are not guaranteed to be located in the same place in every transaction, so you can't just look for the same byte offset in every input to find the signatures. In general, a signature will be 71 or 72 bytes long and begin with the byte 0x30. You can look for things that look like that in transaction inputs to find signatures. However many block explorers also won't show you the signatures unless you enable some sort of advanced mode.

[shadow12348]

As @achow101 said, there is no website of the blockchain. Here's a crass overview.

Block explorers give you information about blocks, that contain transactions.

You can uniquely identify a block by it's block hash (Not transmitted between nodes) that is a double SHA256 hash of the block header.

The block header is an 80 byte field that is a concatenation of information in a block, namely - Version, previous block hash, merkle root (Hierarchical hash of transaction hashes - broadly), timestamp, difficulty and nonce.

Traditionally, legacy bitcoin addresses are encoded by computing RIPEMD160(SHA256(Public Key)) and encoding with Base58Check. Newer form addresses (Segwit & Bech32) use different encoding schemes.

Standard bitcoin scripts use DER encoded signatures not base64.