We would flip a coin and document the required sign. This would place a constraint on the payer, but it should not be a material burden.

e

> On Jan 8, 2015, at 10:55 AM, Amir Taaki <genjix@???> wrote:
>
> oh ok. How can this be established by convention? i.e how would the
> client know whether to use 02 or 03?
>
>> On 01/08/2015 07:49 PM, Eric Voskuil wrote:
>> Maybe I'm missing something, but I thought the idea was that the sign of
>> the ephemeral public key would be established by convention and thereby
>> not be required in the OP_RETURN *and* not require testing of both signs.
>>
>> I'd be concerned that by including the sign byte, and with the payment
>> id at 5 bytes, we would be limiting the nonce space to one byte. That
>> may not be sufficient.
>>
>> e
>>
>>> On 01/08/2015 03:31 AM, Amir Taaki wrote:
>>> Oh if you mean the <P:32>, that doesn't help. It still doubles the
>>> number of rows that clients need to process.
>>> We want to lessen the processing burden on clients, so they can use a
>>> smaller prefix (= more data) to remain more anonymous.
>>>
>>>> On 01/08/2015 12:28 PM, Amir Taaki wrote:
>>>> Yep I got rid of that, that's not staying.
>>>> That's more the type or info byte.
>>>>
>>>>> On 01/08/2015 08:25 AM, Peter Todd wrote:
>>>>>> On Thu, Jan 08, 2015 at 05:11:53AM +0100, Amir Taaki wrote:
>>>>>> This increases the number of client side computations, which reduces the
>>>>>> anonymity. It is trivial for the server to store this data and halves
>>>>>> the computation workload for the client, thereby increasing the
>>>>>> acceptable working dataset & improving anonymity for the client.
>>>>>
>>>>> Good point.
>>>>>
>>>>> However, what about changing the stealth standard itself to not have the
>>>>> sign byte in the OP_RETURN? I believe we've discussed this, along with
>>>>> getting rid of that version byte. We're still at the point where we can
>>>>> change things.
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