1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
|
Return-Path: <truthcoin@gmail.com>
Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org
[172.17.192.35])
by mail.linuxfoundation.org (Postfix) with ESMTPS id 37F9F2C
for <bitcoin-dev@lists.linuxfoundation.org>;
Mon, 22 May 2017 06:17:09 +0000 (UTC)
X-Greylist: whitelisted by SQLgrey-1.7.6
Received: from mail-qt0-f171.google.com (mail-qt0-f171.google.com
[209.85.216.171])
by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 795CEAD
for <bitcoin-dev@lists.linuxfoundation.org>;
Mon, 22 May 2017 06:17:08 +0000 (UTC)
Received: by mail-qt0-f171.google.com with SMTP id v27so94048249qtg.2
for <bitcoin-dev@lists.linuxfoundation.org>;
Sun, 21 May 2017 23:17:08 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025;
h=to:from:subject:message-id:date:user-agent:mime-version
:content-transfer-encoding;
bh=3nHMRCTfQ+XuMv4Yh3Ffa/iDA+HhqpZe44fCXTryHEc=;
b=Nh8mOQKFowadhRXCG0Q5Yrcwuk+31Dj1SLHFNpjxweHzcvCj83QiSLl7lnxZWYZRww
+MWDi+m1UMI1pjw7WRT0ieentSysS47MAHk2Yw4loCsvZeX/hxTECj9Mhdwb4QsWZsy5
aofFJWvijD8TCY6wMxm12gy0K6oACg8kPhGSobctc54p8f+1jml9ThPmn4HMi8pwyYTh
WlyS7jxcCUmjg5PTWSun5u9LNpUhLPjsxMEB94ppIGnsMmA7OjAqt3WQ8ZuvLsP51uKV
t9AxMRe/BaHvogKIHxbQS/86Dh41X3Ty9x9NPe1oeV1b3XkO1PDoh+NpDZoaAaj9QtdU
Ex1Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20161025;
h=x-gm-message-state:to:from:subject:message-id:date:user-agent
:mime-version:content-transfer-encoding;
bh=3nHMRCTfQ+XuMv4Yh3Ffa/iDA+HhqpZe44fCXTryHEc=;
b=pJWyd5+9qPK4EHfFHhUzGLvYBXnv/3yAhtJcvmPMRf/ZbLU4wZ+3fcstEB0xCoiGzE
Ieo25HvTj4O0vnVGCvU7PoIrbKYtk3D9rokyu0GfKq8M6n+kAcE0kAVBlpjUt7YNj7ko
2cr57KGnCoZgmIBPL8oXzyyGPiFkLs/s4TcfX4j7QvZEaT2ZJuu2l5CkOPu65MrlEfeD
7Fj6nyn+KaBL73Zj5sCkpJnoU0uyA+CGyR6UYRbK+JghJ5HnE06u/WKTEzQiYpT8N56Y
FlqopgcwZ7+o42WAySLMhpYsQrGq55+0vDn+Aux8qnSoREMb9tipj+5swTO6GYx+/oF7
iWDg==
X-Gm-Message-State: AODbwcDhyeE91Y58DThh+JDOZzhY6KRD91dN48SyepDu1mnhjaKAlHvQ
P5xeIbsBL34CbdA/K8Jblg==
X-Received: by 10.237.62.136 with SMTP id n8mr19769302qtf.0.1495433827363;
Sun, 21 May 2017 23:17:07 -0700 (PDT)
Received: from [192.168.44.223] ([172.56.28.58])
by smtp.googlemail.com with ESMTPSA id
j65sm4120587qkh.55.2017.05.21.23.17.05
for <bitcoin-dev@lists.linuxfoundation.org>
(version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128);
Sun, 21 May 2017 23:17:06 -0700 (PDT)
To: Bitcoin Dev <bitcoin-dev@lists.linuxfoundation.org>
From: Paul Sztorc <truthcoin@gmail.com>
Message-ID: <24f2b447-a237-45eb-ef9f-1a62533fad5c@gmail.com>
Date: Mon, 22 May 2017 02:17:07 -0400
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:45.0) Gecko/20100101
Thunderbird/45.8.0
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
X-Spam-Status: No, score=-1.5 required=5.0 tests=BAYES_00,DKIM_SIGNED,
DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,
RCVD_IN_SORBS_SPAM autolearn=no version=3.3.1
X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on
smtp1.linux-foundation.org
X-Mailman-Approved-At: Mon, 22 May 2017 10:44:30 +0000
Subject: [bitcoin-dev] Drivechain -- Request for Discussion
X-BeenThere: bitcoin-dev@lists.linuxfoundation.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Bitcoin Protocol Discussion <bitcoin-dev.lists.linuxfoundation.org>
List-Unsubscribe: <https://lists.linuxfoundation.org/mailman/options/bitcoin-dev>,
<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=unsubscribe>
List-Archive: <http://lists.linuxfoundation.org/pipermail/bitcoin-dev/>
List-Post: <mailto:bitcoin-dev@lists.linuxfoundation.org>
List-Help: <mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=help>
List-Subscribe: <https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev>,
<mailto:bitcoin-dev-request@lists.linuxfoundation.org?subject=subscribe>
X-List-Received-Date: Mon, 22 May 2017 06:17:09 -0000
Dear list,
I've been working on "drivechain", a sidechain enabling technology, for
some time.
* The technical info site is here: www.drivechain.info
* The changes to Bitcoin are here:
https://github.com/drivechain-project/bitcoin/tree/mainchainBMM
* A Blank sidechain template is here:
https://github.com/drivechain-project/bitcoin/tree/sidechainBMM
As many of you know, I've been seeking feedback in person, at various
conferences and meetups over the past year, most prominently Scaling
Milan. And I intend to continue to seek feedback at Consensus2017 this
week, so if you are in NYC please just walk up and start talking to me!
But I also wanted to ask the list for feedback. Initially, I was
hesitant because I try not to consume reviewers' scarce time until the
author has put in a serious effort. However, I may have waiting too
long, as today it is actually quite close to a working release.
Scaling Implications
---------------------
This upgrade would have significant scaling implications. Since it is
the case that sidechains can be added by soft fork, and since each of
these chains will have its own blockspace, this theoretically removes
the blocksize limit from "the Bitcoin system" (if one includes
sidechains as part of such a system). People who want a LargeBlock
bitcoin can just move their BTC over to such a network [1], and their
txns will have no longer have an impact on "Bitcoin Core". Thus, even
though this upgrade does not actually increase "scalability" per se, it
may in fact put an end to the scalability debate...forever.
This work includes the relatively new concept of "Blind Merged Mining"
[2] which I developed in January to allow SHA256^2 miners to merge-mine
these "drivechains", even if these miners aren't running the actual
sidechain software. The goal is to prevent sidechains from affecting the
levelness of the mining "playing field". BMM is conceptually similar to
ZooKeeV [3] which Peter Todd sketched out in mid-2013. BMM is not
required for drivechain, but it would address some of the last remaining
concerns.
Total Transaction Fees in the Far Future
-----------------------------------------
Some people feel that a maximum blocksize limit is needed to ensure that
future total equilibrium transaction fees are non-negligible. I
presented [4] on why I don't agree, 8 months ago. The reviewers I spoke
to over the last year have stopped bringing this complaint up, but I am
not sure everyone feels that way.
Juxtaposition with a recent "Scaling Compromise"
-------------------------------------------------
Recently, a scalability proposal began to circulate on social media. As
far as I could tell, it goes something like "immediately activate
SegWit, and then HF to double the nonwitness blockspace to 2MB within 12
months". But such a proposal is quite meager, compared to a "LargeBlock
Drivechain". The drivechain is better on both fronts, as it would not
require a hardfork, and could *almost immediately* add _any_ amount of
extra blockspace (specifically, I might expect a BIP101-like LargeBlock
chain that has an 8 MB maxblocksize, which doubles every two years).
In other words, I don't know why anyone would support that proposal over
mine. The only reasons would be either ignorance (ie, unfamiliarity with
drivechain) or because there are still nagging unspoken complaints about
drivechain which I apparently need to hear and address.
Other Thoughts
---------------
Unfortunately, anyone who worked on the "first generation" of sidechain
technology (the skiplist) or the "second generation" (federated /
Liquid), will find that this is very different.
I will admit that I am very pessimistic about any conversation that
involves scalability. It is often said that "talking politics lowers
your IQ by 25 points". Bitcoin scalability conversations seem to drain
50 points. (Instead of conversing, I think people should quietly work on
whatever they are passionate about until their problem either is solved,
or it goes away for some other reason, or until we all agree to just
stop talking about it.)
Cheers,
Paul
[1] http://www.drivechain.info/faq/#can-sidechains-really-help-with-scaling
[2] http://www.truthcoin.info/blog/blind-merged-mining/
[3] https://s3.amazonaws.com/peter.todd/bitcoin-wizards-13-10-17.log
[4]
https://www.youtube.com/watch?v=YErLEuOi3xU&list=PLw8-6ARlyVciNjgS_NFhAu-qt7HPf_dtg&index=4
|
