IYH Dear Vivek Verma

Transmitting the SHA-256 hash value during communication without requiring additional transmission requires embedding the hash value within the transmitted content itself.

One such possible steganographic approach using least significant bit (LSB) insertion method (see eg Wang 2009 https://www.semanticscholar.org/paper/Steganography-with-Hash-Yu-Wang/408a4908b0a57d8f94a6fcbad32c4f61be157dae#paper-topics )

Works like this (rough overview)

Thank you very much, Professor, for your help.

When transmitting data over a network, using a secure hash function like SHA-256 can provide data integrity and authenticity. Here's how it works:

By using the SHA-256 hash function in this manner, data integrity can be ensured during transmission over a network. Any unauthorized modification of the data would result in a mismatch between the calculated hash at the receiver's end and the received hash, prompting further investigation or data retransmission.

Transmitting the SHA-256 function output without any additional transmission involves sending the result along with the data it's derived from in a single transmission. This can be achieved by including the SHA-256 hash along with the original data. Here's how you can do it:

Here's a simple example in Python:

pythonCopy codeimport hashlib def transmit_data_with_hash(data): # Calculate the SHA-256 hash of the data hash_value = hashlib.sha256(data.encode()).hexdigest() # Transmit data and hash together transmitted_data = data + hash_value # Return the transmitted data return transmitted_data def verify_transmitted_data(transmitted_data): # Separate the data and hash data = transmitted_data[:-64] # Assuming SHA-256 hash length is 64 characters transmitted_hash = transmitted_data[-64:] # Recompute the hash of the received data computed_hash = hashlib.sha256(data.encode()).hexdigest() # Compare computed hash with transmitted hash if computed_hash == transmitted_hash: return "Data integrity verified. No alterations detected." else: return "Data integrity verification failed. Possible alterations detected." # Example usage original_data = "Hello, world!" transmitted_data = transmit_data_with_hash(original_data) print("Transmitted data with hash:", transmitted_data) # Simulating transmission... # Upon receiving transmitted_data, recipient verifies it verification_result = verify_transmitted_data(transmitted_data) print(verification_result)

This code demonstrates how to transmit data along with its SHA-256 hash and verify data integrity upon reception. Remember to adjust the code as needed for your specific use case and programming environment.