The new proposed protocol from IAA that the article references but does not link to: https://arxiv.org/abs/2510.14506

IMO a protocol that doesn't involve automated instantaneous backing up of data on a publicly-referenceable blockchain is worthless due to the apparently legitimate (in the eyes SETI researchers that a former SETI institute chairman references) concern about security services quietly stepping in the way.

(see my other comment for reference)