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
|
Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193]
helo=mx.sourceforge.net)
by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76)
(envelope-from <andyparkins@gmail.com>) id 1RYbVg-0000V3-Bv
for bitcoin-development@lists.sourceforge.net;
Thu, 08 Dec 2011 10:47:28 +0000
Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com
designates 74.125.83.47 as permitted sender)
client-ip=74.125.83.47; envelope-from=andyparkins@gmail.com;
helo=mail-ee0-f47.google.com;
Received: from mail-ee0-f47.google.com ([74.125.83.47])
by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128)
(Exim 4.76) id 1RYbVc-0004gS-JV
for bitcoin-development@lists.sourceforge.net;
Thu, 08 Dec 2011 10:47:28 +0000
Received: by eekb15 with SMTP id b15so1313567eek.34
for <bitcoin-development@lists.sourceforge.net>;
Thu, 08 Dec 2011 02:47:18 -0800 (PST)
Received: by 10.14.9.145 with SMTP id 17mr199615eet.26.1323341238367;
Thu, 08 Dec 2011 02:47:18 -0800 (PST)
Received: from dvr.localnet (mail.360visiontechnology.com. [92.42.121.178])
by mx.google.com with ESMTPS id 17sm16469312eej.3.2011.12.08.02.47.16
(version=TLSv1/SSLv3 cipher=OTHER);
Thu, 08 Dec 2011 02:47:16 -0800 (PST)
From: Andy Parkins <andyparkins@gmail.com>
To: bitcoin-development@lists.sourceforge.net
Date: Thu, 8 Dec 2011 10:47:08 +0000
User-Agent: KMail/1.13.6 (Linux/3.0.0-1-686-pae; KDE/4.6.3; i686; ; )
MIME-Version: 1.0
Content-Type: Text/Plain;
charset="us-ascii"
Content-Transfer-Encoding: 7bit
Message-Id: <201112081047.09082.andyparkins@gmail.com>
X-Spam-Score: -1.6 (-)
X-Spam-Report: Spam Filtering performed by mx.sourceforge.net.
See http://spamassassin.org/tag/ for more details.
-1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for
sender-domain
0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider
(andyparkins[at]gmail.com)
-0.0 SPF_PASS SPF: sender matches SPF record
-0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from
author's domain
0.1 DKIM_SIGNED Message has a DKIM or DK signature,
not necessarily valid
-0.1 DKIM_VALID Message has at least one valid DKIM or DK signature
X-Headers-End: 1RYbVc-0004gS-JV
Subject: [Bitcoin-development] Lowering confirmation requirements and
preventing double spends
X-BeenThere: bitcoin-development@lists.sourceforge.net
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: <bitcoin-development.lists.sourceforge.net>
List-Unsubscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>,
<mailto:bitcoin-development-request@lists.sourceforge.net?subject=unsubscribe>
List-Archive: <http://sourceforge.net/mailarchive/forum.php?forum_name=bitcoin-development>
List-Post: <mailto:bitcoin-development@lists.sourceforge.net>
List-Help: <mailto:bitcoin-development-request@lists.sourceforge.net?subject=help>
List-Subscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>,
<mailto:bitcoin-development-request@lists.sourceforge.net?subject=subscribe>
X-List-Received-Date: Thu, 08 Dec 2011 10:47:28 -0000
Hello,
Another of my crazy ideas:
When a transaction is first broadcast, it should include the hash of the block
it wants to appear after, let's call it's basis block. That block can be
anything the claimer wants; but it allows the miners to add this condition:
the transactions outputs a new transaction claims must be before the new
transaction's basis block.
Consider this block chain fork:
* -- * -- F -- * -- 1 -- 4 -- 5
\
* -- 2 -- 3
Let's say in block 2; I transfer coins from address A to Mt.Gox (or any other
pooled-account online wallet). In block 1 I transfer credit from address A to
address B. In block 3 I transfer credit from Mt.Gox's pool to address B.
The chain at 3 races out first, but eventually the chain at 5 becomes "the
one". If Mt.Gox are foolish enough to broadcast my withdrawl in 3; there is
nothing to stop that same withdrawl making it into 4 (since it comes from a
pooled fund address). Therefore Mt.Gox can't allow such a fast turnaround and
must wait for six confirmations of 2 before allowing use of the funds. That
is an inconvenience for all the honest users.
With my proposed change, the Mt.Gox transaction broadcast at 3 would include
"block 2" as its basis block. Therefore that transaction could never make it
into block 4, as no miner will include a transaction based on block 2 in the
block 4 chain.
Mt.Gox is probably not a good example, as they have problems with fiat to deal
with too. However, for other online wallet accounts it would allow faster
acceptance of received funds, since there is no danger of loss should an
attacker arrange a reorganisation.
This basis block would be optional (implied by the input transactions if it
isn't present); and would only need storing for the pending transactions, so
no incompatible change is needed to the block format.
Andy
--
Dr Andy Parkins
andyparkins@gmail.com
|
