Subject: Re: [bitcoin-dev] Requesting BIP assignment; Flexible Transactions.

From: Peter Todd <[email-masked]>
Date: Tue, 20 Sep 2016 17:56:44 -0400

On Tue, Sep 20, 2016 at 07:15:45PM +0200, Tom via bitcoin-dev wrote:
> === Serialization order===
> 
> The tokens defined above have to be serialized in a certain order for the
> transaction to be well-formatted.  Not serializing transactions in the
> order specified would allow multiple interpretations of the data which
> can't be allowed.

If the order of the tokens is fixed, the tokens themselves are redundant
information when tokens are required; when tokens may be omitted, a simple
"Some/None" flag to mark whether or not the optional data has been omitted is
appropriate.

Also, if you're going to break compatibility with all existing software, it
makes sense to use a format that extends the merkle tree down into the
transaction inputs and outputs.

-- 
https://petertodd.org 'peter'[:-1]@petertodd.org