Schnorr Based Multisig Standards Near Completion for Enhanced Privacy and Lower Transaction Costs
Key Points:
– After years of hard work, the final standards for Schnorr based multisig are almost ready for implementation.
– Traditional multisig methods using CHECKMULTISIG reveal the number of participants and incur higher transaction fees as the number of signers increase.
– MuSig, on the other hand, allows multiple users to collectively generate a single signature and public key, enhancing privacy and reducing transaction costs.
– MuSig2, introduced in 2020, improves user experience by reducing the required communication rounds from three to two.
– The wallet setup for MuSig2 involves collecting participants’ extended public keys (xpubs) and constructing descriptors.
– The signing phase of MuSig2 involves the exchange of nonces and partial signatures among the signers.
– Two BIP drafts, MuSig2 PSBTs and MuSig2 Descriptors, have been proposed for necessary adoption and integration of MuSig2.
– The community is encouraged to review and provide feedback on the BIP drafts to facilitate the standardization of MuSig2.
– Wallet developers and custody solutions have eagerly awaited the completion of MuSig2 standards.
Enhancing Privacy and Reducing Transaction Costs with Schnorr Based Multisig
The development of Schnorr based multisig standards is nearing completion, promising enhanced privacy and lower transaction costs for cryptocurrency users. While traditional multisig methods using CHECKMULTISIG reveal the total number of participants and result in higher transaction fees as the number of signers grow, MuSig provides a solution to these challenges.
Introduced in 2018, MuSig enables a group of users to collectively generate a single signature and public key to validate a transaction. This approach not only enhances privacy by obfuscating the number of participants involved but also lowers the transaction costs for all signers. However, the initial version of MuSig faced a user experience drawback, requiring three rounds of interactive communication between signers.
The introduction of MuSig2 in 2020 addressed this limitation by reducing the required communication rounds from three to two, significantly improving the user experience. The wallet setup for MuSig2 follows established multisig practices, involving the collection of participants’ extended public keys (xpubs) and the construction of descriptors.
The signing phase of MuSig2 involves the exchange of nonces and partial signatures among the signers. During the wallet setup, nonces are generated, added to the Partially Signed Bitcoin Transactions (PSBTs), and shared with the other signers in the first-round message. The nonces received are then used to create a partial signature and sent back to each signer in the second-round message.
To streamline the communication process, a third-party coordinator can be introduced to facilitate the exchange of nonces and partial signatures. Each signer’s nonce is composed of two elliptic curve points, which are transmitted through the PSBTs. While these nonces require careful handling for accuracy and integrity, they do not require secure storage as they are not confidential information. If all partial signatures are valid, the produced Schnorr signatures are deemed valid.
The next steps for the implementation of MuSig2 involve the review and feedback of two BIP drafts proposed by Andy Chow. The MuSig2 PSBTs BIP adds fields for nonces, public keys, and partial signatures in the PSBTs, while the MuSig2 Descriptors BIP provides a method for describing transaction outputs controlled by a MuSig2 wallet. These BIPs and their specifications are crucial for the integration of MuSig2 wallets.
Wallet developers and collaborative custody solutions have eagerly anticipated the standardization of the MuSig2 protocol. With the formalized BIPs in place, the community is encouraged to participate in public discussions, provide feedback, and raise awareness. Blockstream, a leading blockchain technology company, is ready to engage in the review process and contribute to advancing MuSig2 adoption.
Hot Take: Embracing Enhanced Privacy and Cost Efficiency in Multisig Transactions
The imminent implementation of Schnorr based multisig standards marks a significant milestone for the cryptocurrency community, offering enhanced privacy and cost efficiency in multisig transactions. With MuSig2, users can enjoy the benefits of collective signature generation, obfuscating the number of participants and reducing transaction costs. The reduction in required communication rounds further improves the user experience, making MuSig2 an appealing option for wallet developers and collaborative custody solutions. By embracing these standards, the cryptocurrency ecosystem takes a step forward in ensuring privacy and efficiency, fostering wider adoption and trust among users.
