The only way to know it has heard everything is to coordinate withall the other machines to establish that fact.

The downside of using hashes as IDs is that they requiremore space than other schemes. To avoid the storage cost ofexplicitly materialising all of the hashes, it would be possibleto design a compression scheme that recomputes hasheswhen necessary, and store only the information necessaryto perform this recomputation.

As we discussed in #matrix-spec, since "rooms" are so much more than "chat rooms," and are really a DAG of events

but I also have one: a verifiable data tree, not just a chain. So in my view, a verifiable data tree is the solution, not a shared blockchain

Power DAG

This algorithm has the downside thatmany updates may be sent to nodes that have already re-ceived them from another node, wasting network bandwidth

It is clear thatthis approach will bring some benefits

The depth of a block in a blocklaceis the length of the maximal path emanating from it

The Battle of Köse Dağ was fought between the Sultanate of Rum ruled by the Seljuq dynasty and the Mongol Empire on June 26, 1243, at the defile of Kösedağ, a location between Erzincan and Gümüşhane in modern northeastern Turkey.[10][11] The Mongols achieved a decisive victory.