Merkleise beacon chain blocks

[JustinDrake]

Currently beacon chain blocks are hashed as monoliths. This is not friendly to light clients because beacon chain blocks could be quite large (as currently specced, attestations and specials are unbounded arrays of records).

My suggestion is to hash the individual fields in a BeaconChainBlock (of which there are 8) and then consider those as leaves of a Merkle tree. We then replace ancestor_hashes, oblique_parent_hashes, justified_block_hash, etc. with ancestor_roots, oblique_parent_roots, justified_block_root, etc.

[vbuterin]

I'd personally prefer to hold off on making special-case decisions like that until we decide whether the special-case route is even the correct route in the first place. The alternative is that we create a general-purpose merkle-hashing algorithm for SImpleSerialize, and that way we get beacon chain blocks and the active and crystallized state.

[JustinDrake]

For sure, (re)using the same logic as for state merkle-hashing is the way forward. (I'm just suggesting moving away from naive hashing for beacon blocks.)

[vbuterin]

Agree! And I'm suggesting doing what you want as part of a common general strategy for moving away from naive hashing for everything :)

[mkalinin]

It would be nice to make validator set a part of that strategy too.

[vbuterin]

#54

[JustinDrake]

Closing in favour of #54 👍