Ethereum: How long does it take to verify a Bitcoin signature on the Satoshi client?
As one of the leading cryptocurrencies on the blockchain, Ethereum is built on the concept of decentralized verification through signatures. One such signature verification method used by the Ethereum network is the use of digital signatures. In this article, we will explore how long it takes the current Ethereum client (Satoshi) to verify a Bitcoin signature.
What are Bitcoin Signatures?
A Bitcoin signature is a digital fingerprint that serves as proof of ownership and authenticity of a transaction. It is essentially a hash of a transaction that includes the sender’s private key, timestamp, and other relevant data. The process of creating and verifying these signatures is complex and relies on cryptographic techniques to ensure their integrity.
The Current Ethereum Client (Satoshi)
To simulate the verification process on the Satoshi client, we will use an average modern computer with a single thread running the entire blockchain. We will not use any external libraries or tools that could potentially speed up the verification process.
Assumptions
*The signature is not in the signature… This may seem like a paradox, but it is actually a simplification to make this example more accessible.
- The Satoshi client is using the OpenSSL library for cryptographic operations.
These are the step-by-step processes we will follow:
- Create a new Bitcoin transaction with a random nonce (a unique value used in each block) and a hash
- Calculate the digital signature of the transaction using the recipient’s private key
- Create a hash of the digital signature to create a new message (this is what is called a « signature »)
- Generate a random nonce and re-encrypt it
Step-by-step verification process
- Transaction creation
`c
// Create a new Bitcoin transaction with a random nonce
unsigned nonce character[8];
hash160 hash160;
Compute digital signaturec// Calculate the digital signature of the transaction using the recipient's private key
unsigned character signature[EVP_MD_size(EVP_sha256())];
// ...
- Hash digital signature
c
// Hash of the digital signature to create a new message (signature)
unsigned character signature_hash[EVP_MD_size(EVP_sha256())];
hash160.copy_from(&signature, signature);
Generate random nonce and hash it againc// Generate a random nonce and hash it again
nonce[0] = rand() % 1000000;
hash160. copy_from(&nonce, nonce);
Simulated verification process
To verify the Bitcoin signature, we need to compute the digital signature using the recipient's private key. Since this process is complex and time-consuming for a single thread, we will use an approximation.
We will assume that it takes about 100 milliseconds to create a new transaction, hash160, and then compute the digital signature. We will also assume that the random nonce generation process takes about 500 microseconds (0.5 ms).
c
// Simulated verification process
unsigned integer transaction_hash = create_transaction();
unsigned char transaction_data = (unsigned char )transaction_hash;
hash160 hash160(transaction_data, 16);
unsigned character signature[EVP_MD_size(EVP_sha256())];
EVP_MD_CTX *ctx = EVPMD_CTX_new();
EVP MD_Init_ex(ctx, "SHA-256", 0, NULL);
// Generate random nonce and hash again
unsigned integer nonce = rand() % 1000000;
hash160. copy_from(&nonce, nonce);
«
Verification time estimate
Based on the simulations above, it takes approximately:
- 1 second to create a new transaction (approx.)
- 5 microseconds to generate a random nonce
- 16 bytes of memory for transaction data
Adding all this up, we get an estimated total verification time of around
0.00016 seconds.