State minimization in MuSig2 signing sessions

State minimization in MuSig2 signing sessions

Original Postby real-or-random

Posted on: March 7, 2024 12:26 UTC

In the realm of cryptographic implementation, specifically regarding the MuSig2 protocol within the Bitcoin Core's secp256k1 library, there arises a nuanced differentiation between session_id and rand_root.

A misunderstanding has been highlighted, stemming from the interchangeable use of these terms in various contexts. The confusion is further elucidated through an insightful exchange, addressing the critical aspect that a new session, denoted by a fresh rand_root, ensures the integrity and distinctiveness of the session, even if it retains the original session_id. This distinction is paramount in maintaining the cryptographic standards and security protocols inherent to the implementation.

Furthermore, the dialogue sheds light on an underlying issue where the term session_id has been used in place of what is conceptually referred to as rand_root in the C implementation of MuSig2. This terminological overlap has led to misunderstandings not only amongst contributors but also potentially affecting the broader community engaging with the codebase. The recognition of this confusion has prompted discussions and clarifications, as evidenced by comments on a pertinent pull request within the project's repository (see the discussion here). This scenario underscores the importance of clear and unambiguous terminology in the development and documentation of cryptographic protocols, ensuring both accuracy and ease of understanding for all stakeholders involved.