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
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
|
Return-Path: <adam.back@gmail.com>
Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org
[172.17.192.35])
by mail.linuxfoundation.org (Postfix) with ESMTPS id 018957AA
for <bitcoin-dev@lists.linuxfoundation.org>;
Tue, 11 Jul 2017 16:50:03 +0000 (UTC)
X-Greylist: whitelisted by SQLgrey-1.7.6
Received: from mail-qk0-f171.google.com (mail-qk0-f171.google.com
[209.85.220.171])
by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 6FADC3FF
for <bitcoin-dev@lists.linuxfoundation.org>;
Tue, 11 Jul 2017 16:49:59 +0000 (UTC)
Received: by mail-qk0-f171.google.com with SMTP id 16so8520475qkg.2
for <bitcoin-dev@lists.linuxfoundation.org>;
Tue, 11 Jul 2017 09:49:59 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025;
h=mime-version:reply-to:in-reply-to:references:from:date:message-id
:subject:to:cc;
bh=Bo+0zgGs3GtPTn3swVWBeSpbuIq8g37xkx7XFUt4sIo=;
b=vcHlMPcBT7jPvQrn1mdkQEmc2gUgW6/HKQct3zwbsE902EowTBr4hheaiVotyW44+C
vME2lZSY9QGXyHPu7cMoqGzlsHhhxRGVfxL25ryuuFly0EeuOXYfpOP1nIhGcXFsuH2E
JBIq5AqqwznhST8C+Ai58k24AMfIne9Brc1ovuM88w4HP/2k9W5xuXe3mJbCr8FaAU69
2VN4L4kEdBoOgT601goIsT8WA/KzlIE2VBX47Pv75pH3DLRoQ2/13aGDgZWgoxBHz43m
Yv4nG/KwyZn6UCuUgpxcB5F452urpZUxBnUqif7vhDoCy2rkxPrmMJLtPJaHa3oZwoEs
J24g==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
d=1e100.net; s=20161025;
h=x-gm-message-state:mime-version:reply-to:in-reply-to:references
:from:date:message-id:subject:to:cc;
bh=Bo+0zgGs3GtPTn3swVWBeSpbuIq8g37xkx7XFUt4sIo=;
b=R49eK5vd0OGHyCxXT2ZOwu5gnrbT9JV1UFkweTRizXtWMf7RsWaoKb7zR7ZoGW+RCL
1O4ZpxrmEaoLQZdTsUfdC6/Rt0T2cExEsomhvfxMS+UWkdc9h1vbZYDTQKA+ts7NNazw
xQ8QDf7m6Yo235lbKR/qr9iVVdxalt+EFlosjNFgoF5t56eFQ4g2ElwSbeurRuySnDrN
+m40sM/eKVKt5xkg/5jUZfkFC0NM/UM7YsJxcdYcDRZbBMuaLGed6Tv/etT7+pVvfkO8
tYenwL+4aYcO0pnuVZyRkpKz31bxRoyPGfzOAVK4NLOSSr0SSA4VXxwW0eifqoKvwXQx
RHdA==
X-Gm-Message-State: AIVw113SH9YODrDJ7yc2c8Ud056zS0jfTKGZUJgxgwCdCwjqxNq2dRxw
PNgXy8MucThPNrnnl0hKsdbrLIm+10Wh
X-Received: by 10.200.42.181 with SMTP id b50mr1145609qta.122.1499791798348;
Tue, 11 Jul 2017 09:49:58 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.12.132.34 with HTTP; Tue, 11 Jul 2017 09:49:57 -0700 (PDT)
Reply-To: adam@cypherspace.org
In-Reply-To: <CAGL6+mHQZ3UP10msk65OO+Uk0hn7j+dkmJap_M7FgWfSZaYYJQ@mail.gmail.com>
References: <0119661e-a11a-6d4b-c9ec-fd510bd4f144@gmail.com>
<CAGL6+mHQZ3UP10msk65OO+Uk0hn7j+dkmJap_M7FgWfSZaYYJQ@mail.gmail.com>
From: Adam Back <adam.back@gmail.com>
Date: Tue, 11 Jul 2017 17:49:57 +0100
Message-ID: <CALqxMTEEGg1Y03_3on1Ggjb_42UXbDcqL4sb0xZ-OTid+ThzAA@mail.gmail.com>
To: Chris Stewart <chris@suredbits.com>,
Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
Content-Type: text/plain; charset="UTF-8"
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: Tue, 11 Jul 2017 21:10:04 +0000
Subject: Re: [bitcoin-dev] Updating the Scaling Roadmap
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: Tue, 11 Jul 2017 16:50:03 -0000
Separate from scale, there is utility to a hard-fork to fix wish-list
bugs that cant be reasonably fixed via soft-fork. The spoonnet
proposal fixes a good number of interesting bugs. Spoonnet and
several other HF research proposals can be found here
https://bitcoinhardforkresearch.github.io/ Part of the research on HF
is about safe deployment methods which is obviously the other main
consideration. It seems to me likely that if the HF were to focus on
bug fixes, and not mix in new tradeoffs of security vs scale, it would
more easily reach consensus.
Adam
On 11 July 2017 at 17:03, Chris Stewart via bitcoin-dev
<bitcoin-dev@lists.linuxfoundation.org> wrote:
> Concept ACK.
>
> I think you are overstating the readiness of drivechains though. I think the
> optimistic estimate for drivechains to be ready for bitcoin core is a year
> out from today. More likely the date should be early 2018. Still a lot of
> work to be done! :-)
>
> Also I don't know if I would put a hard fork suggestion in the scaling map.
> If drivechains are successful they should be viewed as the way we scale --
> not hard forking the protocol. Do you still have capacity concerns if
> drivechains are successful?
>
> -Chris
>
> On Mon, Jul 10, 2017 at 11:50 AM, Paul Sztorc via bitcoin-dev
> <bitcoin-dev@lists.linuxfoundation.org> wrote:
>>
>>
>> Summary
>> =========
>>
>> In my opinion, Greg Maxwell's scaling roadmap [1] succeeded in a few
>> crucial ways. One success was that it synchronized the entire Bitcoin
>> community, helping to bring finality to the (endless) conversations of
>> that time, and get everyone back to work. However, I feel that the Dec
>> 7, 2015 roadmap is simply too old to serve this function any longer. We
>> should revise it: remove what has been accomplished, introduce new
>> innovations and approaches, and update deadlines and projections.
>>
>>
>> Why We Should Update the Roadmap
>> =================================
>>
>> In a P2P system like Bitcoin, we lack authoritative info-sources (for
>> example, a "textbook" or academic journal), and as a result
>> conversations tend to have a problematic lack of progress. They do not
>> "accumulate", as everyone must start over. Ironically, the scaling
>> conversation _itself_ has a fatal O(n^2) scaling problem.
>>
>> The roadmap helped solve these problems by being constant in size, and
>> subjecting itself to publication, endorsement, criticism, and so forth.
>> Despite the (unavoidable) nuance and complexity of each individual
>> opinion, it was at least globally known that X participants endorsed Y
>> set of claims.
>>
>> Unfortunately, the Dec 2015 roadmap is now 19 months old -- it is quite
>> obsolete and replacing it is long overdue. For example, it highlights
>> older items (CSV, compact blocks, versionbits) as being _future_
>> improvements, and makes no mention of new high-likelihood improvements
>> (Schnorr) or mis-emphasizes them (LN). It even contains mistakes (SegWit
>> fraud proofs). To read the old roadmap properly, one must already be a
>> technical expert. For me, this defeats the entire point of having one in
>> the first place.
>>
>> A new roadmap would be worth your attention, even if you didn't sign it,
>> because a refusal to sign would still be informative (and, therefore,
>> helpful)!
>>
>> So, with that in mind, let me present a first draft. Obviously, I am
>> strongly open to edits and feedback, because I have no way of knowing
>> everyone's opinions. I admit that I am partially campaigning for my
>> Drivechain project, and also for this "scalability"/"capacity"
>> distinction...that's because I believe in both and think they are
>> helpful. But please feel free to suggest edits.
>>
>> I emphasized concrete numbers, and concrete dates.
>>
>> And I did NOT necessarily write it from my own point of view, I tried
>> earnestly to capture a (useful) community view. So, let me know how I did.
>>
>> ==== Beginning of New ("July 2017") Roadmap Draft ====
>>
>> This document updates the previous roadmap [1] of Dec 2015. The older
>> statement endorsed a belief that "the community is ready to deliver on
>> its shared vision that addresses the needs of the system while upholding
>> its values".
>>
>> That belief has not changed, but the shared vision has certainly grown
>> sharper over the last 18 months. Below is a list of technologies which
>> either increase Bitcoin's maximum tps rate ("capacity"), or which make
>> it easier to process a higher volume of transactions ("scalability").
>>
>> First, over the past 18 months, the technical community has completed a
>> number of items [2] on the Dec 2015 roadmap. VersonBits (BIP 9) enables
>> Bitcoin to handle multiple soft fork upgrades at once. Compact Blocks
>> (BIP 152) allows for much faster block propagation, as does the FIBRE
>> Network [3]. Check Sequence Verify (BIP 112) allows trading partners to
>> mutually update an active transaction without writing it to the
>> blockchain (this helps to enable the Lightning Network).
>>
>> Second, Segregated Witness (BIP 141), which reorganizes data in blocks
>> to handle signatures separately, has been completed and awaits
>> activation (multiple BIPS). It is estimated to increase capacity by a
>> factor of 2.2. It also improves scalability in many ways. First, SW
>> includes a fee-policy which encourages users to minimize their impact on
>> the UTXO set. Second, SW achieves linear scaling of sighash operations,
>> which prevents the network from crashing when large transactions are
>> broadcast. Third, SW provides an efficiency gain for everyone who is not
>> verifying signatures, as these no longer need to be downloaded or
>> stored. SegWit is an enabling technology for the Lightning Network,
>> script versioning (specifically Schnorr signatures), and has a number of
>> benefits which
>> are unrelated to capacity [4].
>>
>> Third, the Lightning Network, which allows users to transact without
>> broadcasting to the network, is complete [5, 6] and awaits the
>> activation of SegWit. For those users who are able to make a single
>> on-chain transaction, it is estimated to increase both capacity and
>> scalability by a factor of ~1000 (although these capacity increases will
>> vary with usage patterns). LN also greatly improves transaction speed
>> and transaction privacy.
>>
>> Fourth, Transaction Compression [7], observes that Bitcoin transaction
>> serialization is not optimized for storage or network communication. If
>> transactions were optimally compressed (as is possible today), this
>> would improve scalability, but not capacity, by roughly 20%, and in some
>> cases over 30%.
>>
>> Fifth, Schnorr Signature Aggregation, which shrinks transactions by
>> allowing many transactions to have a single shared signature, has been
>> implemented [8] in draft form in libsecp256k1, and will likely be ready
>> by Q4 of 2016. One analysis [9] suggests that signature aggregation
>> would result in storage and bandwidth savings of at least 25%, which
>> would therefore increase scalability and capacity by a factor of 1.33.
>> The relative savings are even greater for multisignature transactions.
>>
>> Sixth, drivechain [10], which allows bitcoins to be temporarily
>> offloaded to 'alternative' blockchain networks ("sidechains"), is
>> currently under peer review and may be usable by end of 2017. Although
>> it has no impact on scalability, it does allow users to opt-in to
>> greater capacity, by moving their BTC to a new network (although, they
>> will achieve less decentralization as a result). Individual drivechains
>> may have different security tradeoffs (for example, a greater reliance
>> on UTXO commitments, or MimbleWimble's shrinking block history) which
>> may give them individually greater scalability than mainchain Bitcoin.
>>
>> Finally, the capacity improvements outlined above may not be sufficient.
>> If so, it may be necessary to use a hard fork to increase the blocksize
>> (and blockweight, sigops, etc) by a moderate amount. Such an increase
>> should take advantage of the existing research on hard forks, which is
>> substantial [11]. Specifically, there is some consensus that Spoonnet
>> [12] is the most attractive option for such a hardfork. There is
>> currently no consensus on a hard fork date, but there is a rough
>> consensus that one would require at least 6 months to coordinate
>> effectively, which would place it in the year 2018 at earliest.
>>
>> The above are only a small sample of current scaling technologies. And
>> even an exhaustive list of scaling technologies, would itself only be a
>> small sample of total Bitcoin innovation (which is proceeding at
>> breakneck speed).
>>
>> Signed,
>> <Names Here>
>>
>> [1]
>>
>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2015-December/011865.html
>> [2] https://bitcoincore.org/en/2017/03/13/performance-optimizations-1/
>> [3] http://bluematt.bitcoin.ninja/2016/07/07/relay-networks/
>> [4] https://bitcoincore.org/en/2016/01/26/segwit-benefits/
>> [5]
>>
>> http://lightning.community/release/software/lnd/lightning/2017/05/03/litening/
>> [6] https://github.com/ACINQ/eclair
>> [7] https://people.xiph.org/~greg/compacted_txn.txt
>> [8]
>>
>> https://github.com/ElementsProject/secp256k1-zkp/blob/d78f12b04ec3d9f5744cd4c51f20951106b9c41a/src/secp256k1.c#L592-L594
>> [9] https://bitcoincore.org/en/2017/03/23/schnorr-signature-aggregation/
>> [10] http://www.drivechain.info/
>> [11] https://bitcoinhardforkresearch.github.io/
>> [12]
>>
>> https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2017-February/013542.html
>>
>> ==== End of Roadmap Draft ====
>>
>> In short, please let me know:
>>
>> 1. If you agree that it would be helpful if the roadmap were updated.
>> 2. To what extent, if any, you like this draft.
>> 3. Edits you would make (specifically, I wonder about Drivechain
>> thoughts and Hard Fork thoughts, particularly how to phrase the Hard
>> Fork date).
>>
>> Google Doc (if you're into that kind of thing):
>>
>> https://docs.google.com/document/d/1gxcUnmYl7yM0oKR9NY9zCPbBbPNocmCq-jjBOQSVH-A/edit?usp=sharing
>>
>> Cheers,
>> Paul
>>
>>
>> _______________________________________________
>> bitcoin-dev mailing list
>> bitcoin-dev@lists.linuxfoundation.org
>> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>>
>
>
> _______________________________________________
> bitcoin-dev mailing list
> bitcoin-dev@lists.linuxfoundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev
>
|