About the PayToAnchor Script v28.0: A Guide

Bitcoin, the first decentralized cryptocurrency, has undergone significant upgrades to its core blockchain technology. The latest version of Bitcoin, v28.0, introduces a new script called PayToAnchor (PTA). In this article, we will delve into the world of PayToAnchor and explore its inner workings.

What is PayToAnchor?

PayToAnchor is a script that allows anchor nodes to be used as payment addresses for transactions on the Bitcoin blockchain. Anchor nodes are responsible for verifying transaction data, creating new blocks, and maintaining the integrity of the blockchain. Using PTAs, these nodes can now act as pay-to-anchors, allowing them to receive payments from other users without having to broadcast a full transaction.

PayToAnchor v28.0 Script

The PayToAnchor v28.0 script is defined in the Bitcoin source repository’s script.cpp file. Here’s a high-level overview of the script:

#include 
#include "script/script.h"
namespace bitcoin {
struct anchor_script {
uint8_t paytoanchor_code[18];
uint8_t paytoanchor_data_size;
AnchorScriptType paytoanchor_type;
};
struct paytoanchor_script {
PayToAnchor paytoanchor;
};
PAYTOANCHOR_SCRIPT(paytoanchor_script)
: paytoanchor(AnchorScriptType::PayToAnchor) {}
} // namespace bitcoin

The variable paytoanchor is an instance of the enum AnchorScriptType::PayToAnchor, which determines the type of anchor node this script represents.

PaytoAnchor Script Data Structure

The paytoanchor_script structure contains two members:

• paytoanchor_code: An 18-byte array containing the pay-to-anchors code used for transaction data.

• paytoanchor_data_size: An unsigned int specifying the size of the pay-to-anchors data.

• paytoanchor_type: An enum value that determines the type of anchor node.

AnchorScriptType

The AnchorScriptType enum defines two values: PayToAnchor and Unknown Anchor (UAN). The value PayToAnchor indicates that this script represents a pay-to-anchor node, while UAN is used when no specific anchor node type is specified.

PaytoAnchor on the Bitcoin Network

When a transaction is broadcast to the Bitcoin network using the PayToAnchor v28.0 script, it will be split into three parts:

• The transaction data itself.

• A pay-to-anchor header (PAYTOANCHOR_SCRIPT) that specifies the type of anchor node and its associated code.

• The remaining transaction data.

The pay-to-anchor header is encoded in two 32-byte blocks: paytoanchor_code and paytoanchor_data_size. The first block contains the pay-to-anchors code, while the second block contains the pay-to-anchors data size.

Conclusion

In conclusion, the v28.0 PayToAnchor script is a crucial component of Bitcoin’s scalability improvements. By enabling anchor nodes to act as payment addresses, this script facilitates the creation of new blockchains and increases the overall functionality of the Bitcoin network. Understanding the underlying mechanics of PayToAnchor scripts can help developers working on Bitcoin-related projects develop more effective solutions to improve scalability and usability.

Additional Resources

For further reading, please refer to the following resources:

• Bitcoin Core 27.1 Documentation: <

• Bitcoin Core 28.0 Documentation: <