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From: Btc Drak <btcdrak@gmail.com>
Date: Fri, 4 Sep 2015 16:40:26 +0100
Message-ID: <CADJgMzvM4ZfjktS9KwbtJ52x5Ea75OXy9c_ngTCXyAw7uDyB1g@mail.gmail.com>
To: Simon Liu <simon@bitcartel.com>
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Cc: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] BIP 100 specification
Precedence: list

If you read between the lines of what was recently changed and why
(reducing to 2MB), it seems reasonable to assume BIP101's allowance
opens up some of the attack vector again.

On Fri, Sep 4, 2015 at 4:37 PM, Simon Liu via bitcoin-dev
<bitcoin-dev@lists.linuxfoundation.org> wrote:
> Maybe grab some code from BIP101 ?  It permits block messages > 2MB,
> while retaining the current limit of 2 MB imposed on other network
> messages.  The 32 MB limit was patched a few months ago.
>
> Links to code:
>
> https://www.reddit.com/r/bitcoinxt/comments/3in5mm/psa_correction_to_btcchina_letter_which_states/
>
>
>
> On 09/04/2015 12:53 AM, Andy Chase via bitcoin-dev wrote:
>> The 32Mb limit is
>> here: https://github.com/bitcoin/bitcoin/blob/master/src/serialize.h#L25
>>
>> It's to keep the message size small enough that messages can be
>> serialized in memory.
>>
>> Jeff if you decide to lift the 32MB limit (you really should, unless
>> your plan is to potentially hard force another Blocksize discussion
>> again which might be okay). I suggest having the 32MB ceiling auto-raise
>> according to a exponential factor (1.5?) starting 1 year from now.
>>
>> Basically hard limit ceiling 2016-2017: 32 MB
>> Hard limit ceiling 2018+: 32*((currentYear-2018)*1.5) MB
>>
>> The factor could be 2 like BIP-101 but I imagine you will want to be
>> more conservative. The delay time could also be longer if you think it
>> will take longer to fix the message size issue across all implementations.
>>
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