Re: [Trans] Verifying inclusion proof

[Phillip Hallam-Baker <[e-mail]>]

On Mon, Jun 29, 2015 at 2:21 PM, Stephen Kent <[e-mail]> wrote:

> Ben,
>
>  On 28 June 2015 at 16:05, Stephen Kent<[e-mail]>  wrote:
>>
>>> IETF standards need to be unambiguous. Code is very helpful, but it is
>>> not a
>>> substitute
>>> for a rigorous description of how to resolve the issue that Onderj
>>> raised.
>>>
>> Whilst I am not necessarily opposed to that, there has to be a point
>> at which you stop explaining what can be worked out given existing
>> information. The RFC does state how the hash is calculated, from which
>> it is clear what the placement of each node is in the hash
>> calculation.
>>
> My comment is based on the question that was posed by someone for
> whom it was not clear. If most other (independent) implementers find
> the text clear enough, OK.
>
> Citing a tech paper is not the preferred approach for IETF docs. We
> often reproduce info that is available via other means, so that RFCs
> are as self-contained as possible.


As a general rule, placement and organization does not matter.

If someone gives you the apex value of the tree and the sequence of branch
values and whether they are left or right, you have all the info required
to verify.


While the spec says 'Merkle tree', all that is required for interop is to
deliver the correct branches.