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Wed, 31 Jul 2019 14:53:25 +0000 Received: from DB6PR10MB1832.EURPRD10.PROD.OUTLOOK.COM (10.152.0.53) by HE1EUR01FT038.mail.protection.outlook.com (10.152.1.93) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA384) id 15.20.2136.14 via Frontend Transport; Wed, 31 Jul 2019 14:53:25 +0000 Received: from DB6PR10MB1832.EURPRD10.PROD.OUTLOOK.COM ([fe80::cc12:47f0:aa33:6b70]) by DB6PR10MB1832.EURPRD10.PROD.OUTLOOK.COM ([fe80::cc12:47f0:aa33:6b70%3]) with mapi id 15.20.2115.005; Wed, 31 Jul 2019 14:53:25 +0000 From: "Kenshiro []" To: Alistair Mann , Bitcoin Protocol Discussion Thread-Topic: [bitcoin-dev] Add a moving checkpoint to the Bitcoin protocol Thread-Index: AQHVR5sdyaW9NUkjL067/8euo+yr/KbkwSWAgAAJxaeAAAS0tw== Date: Wed, 31 Jul 2019 14:53:25 +0000 Message-ID: References: , <28454621.Lge63Ifvux@dprfs-d5766>, In-Reply-To: Accept-Language: en-US, es-ES Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-incomingtopheadermarker: OriginalChecksum:8D9A6F0B07AD1BD363E5DEC95F82267BB9B0E56D03E6E637D52D31535394A851; 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charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable P.S.: To be clearer, in this example I set an N value of 144 blocks, which = is approximately 24 hours. ________________________________ From: Kenshiro [] Sent: Wednesday, July 31, 2019 16:40 To: Alistair Mann ; Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] Add a moving checkpoint to the Bitcoin protocol >>> How would a (potentially, state-sponsored) netsplit lasting longer than= N be handled? It would be detected by the community much before reaching the reorg limit = of N blocks (it's 24 hours) so nodes could stop until the netsplit is fixed= . In the extreme case no one notice the network split during more than N bloc= ks (24 hours) and there are 2 permanent forks longer than N, nodes from one= branch could delete their local history so they would join the other branc= h. Regards, ________________________________ From: Alistair Mann Sent: Wednesday, July 31, 2019 15:59 To: Kenshiro [] ; Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] Add a moving checkpoint to the Bitcoin protocol On Wednesday 31 Jul 2019 12:28:58 Kenshiro [] via bitcoin-dev wrote: > I would like to propose that a "moving checkpoint" is added to the Bitcoi= n > protocol. It's a very simple rule already implemented in NXT coin: > > - A node will ignore any new block under nodeBlockHeight - N, so the > blockchain becomes truly immutable after N blocks, even during a 51% atta= ck > which thanks to the moving checkpoint can't rewrite history older than th= e > last N blocks. How would a (potentially, state-sponsored) netsplit lasting longer than N b= e handled? -- Alistair Mann --_000_DB6PR10MB183271245AAE84FB9AC96474A6DF0DB6PR10MB1832EURP_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
P.S.: To be clearer, in this example I set an N value of 144 blocks, which = is approximately 24 hours.

From: Kenshiro [] <tensi= am@hotmail.com>
Sent: Wednesday, July 31, 2019 16:40
To: Alistair Mann <al@pectw.net>; Bitcoin Protocol Discussion = <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Add a moving checkpoint to the Bitcoin pr= otocol
 
>>> How would a (potentially, state-sponsored) netsplit= lasting longer than N be
handled?  

It would be detected by the community much before reaching the reorg = limit of N blocks (it's 24 hours) so nodes could stop until the netsplit is= fixed. 

In the extreme case no one notice the network split during more than = N blocks (24 hours) and there are 2 permanent forks longer than N, n= odes from one branch could delete their local history so they would join th= e other branch.

Regards,


From: Alistair Mann <a= l@pectw.net>
Sent: Wednesday, July 31, 2019 15:59
To: Kenshiro [] <tensiam@hotmail.com>; Bitcoin Protocol Discus= sion <bitcoin-dev@lists.linuxfoundation.org>
Subject: Re: [bitcoin-dev] Add a moving checkpoint to the Bitcoin pr= otocol
 
On Wednesday 31 Jul 2019 12:28:58 Kenshiro [] vi= a bitcoin-dev wrote:

> I would like to propose that a "moving checkpoint" is added = to the Bitcoin
> protocol. It's a very simple rule already implemented in NXT coin:
>
> - A node will ignore any new block under nodeBlockHeight - N, so the > blockchain becomes truly immutable after N blocks, even during a 51% a= ttack
> which thanks to the moving checkpoint can't rewrite history older than= the
> last N blocks.

How would a (potentially, state-sponsored) netsplit lasting longer than N b= e
handled? 
--
Alistair Mann

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