Blockdaemon Blog

Partial Signatures For Drop-In Replacement of MultiSig

Wallet
Feb 18, 2020
By:
Frank
Wiener
&
It is well-understood that having multiple approvers on blockchain transactions is important for strong security. As an example, Bitcoin supports a mechanism called MultiSig, where, 3 public keys are associated with a UTX (unspent transaction) and to spend those funds digital signatures from 2 or 3 of the associated private keys must be provided.

It is well-understood that having multiple approvers on blockchain transactions is important for strong security. As an example, Bitcoin supports a mechanism called MultiSig, where, 3 public keys are associated with a UTX (unspent transaction) and to spend those funds digital signatures from 2 or 3 of the associated private keys must be provided.

Want to hear more about how Blockdaemon can help you with your Blockchain journey? Contact us today to chat more about our blockchain solutions

However, MultiSig has a number of drawbacks which are essentially due to the fact that MultiSig is implemented in and published on the public bitcoin blockchain.

An alternative solution which supports multiple approvers but with none of those drawbacks are MPC-based threshold signatures schemes, such as Blockdaemon ThresholdSig™ where everything happens off-chain.

A challenge with MPC protocols is that typical implementations require all participants (or at least the number which is required to sign) to be online concurrently. This concurrency requirement might be acceptable for certain use cases, but if a threshold signature scheme is to replace an existing MultiSig-based solution this potential requirement can be a challenge.

The reason is that with a MultiSig wallet each signer can add their signature without any interaction with the other signers. So, to replace a MultiSig-based wallet the new solution must have this same property that each signer can add her part of the signature independent of the status of other signers.

Blockdaemon ThresholdSig allows for autonomous approvals through a feature called partial signatures. Instead of generating full signatures as in MultiSig, Blockdaemon ThresholdSig lets each signer generate a partial signature locally, independent of the online or offline status of other approvers. These partial signatures can then be aggregated into a full signature. In this way Blockdaemon ThresholdSig offers a straightforward to support the same workflow used in a MultiSig-based solution, with the added benefits of consistent support across all DA types, and with better security.

Contact our sales team to learn how the Blockdaemon Wallet can improve your security.

Share
Get Started

Ready to build your blockchain business?

Fill out the form to connect with one of our product experts and learn how Blockdaemon can help you unlock the power of blockchain.

Thank you for connecting with Blockdaemon; we look forward to assisting with your blockchain endeavors.
Oops! Something went wrong while submitting the form.