In Ark, all digital tx outputs (vtxos) are literally outputs on the leaf txs of a binary tree of transactions. The explanation for that is two-fold: so {that a} single individual exiting would not need to broadcast all of the vtxo outputs for all vtxos within the Ark tx and in order that within the case of mass exit, the method smoothens out and there’s extra time for everybody to exit slowly.
You may consider the vtxo tree of a tree of transactions that every have one enter and two outputs and like that they kind a tree construction. Consider these transactions as transactions which can be already pre-specified upfront. They’ll both be pre-signed or pre-specified utilizing introspection opcodes. Which means that all these transactions are legitimate Bitcoin transactions and will all in concept be confirmed. Nevertheless, they do not carry any payment and nobody has an incentive to broadcast them to the community.
Such a tree may appear to be this:
On this tree, there are 4 leaves, A, B, C and D; they’re precise legitimate transaction outputs and we’ll name them “vtxos”. Digital as a result of they aren’t confirmed but, however may be confirmed if they might be mined.
Now, for the vtxo A to be confirmed, for example as a result of its proprietor desires to spend the cash on-chain, all of the transactions going from the on-chain output (the top-most “cov”) in direction of the leaf A need to be confirmed on the chain.
As a result of this can be a binary tree, the variety of nodes in a department is log2(n) the place n is the variety of leaves, plus one for the leaf itself. So which means log2(4) + 1 is 3 transactions to be confirmed.