đź“… Original date posted:2012-03-06
đź“ť Original message:On Tue, Mar 6, 2012 at 6:05 PM, Gregory Maxwell <gmaxwell at gmail.com> wrote:
> On Fri, Mar 2, 2012 at 2:57 PM, Watson Ladd <wbl at uchicago.edu> wrote:
>> I am proposing a new opcode for the purposes of anonymous
>> transactions. This new opcode enables scripts to be given proof that
>> the receiver can carry out or has carried out a previous transaction.
>> I'm currently working on a paper that discusses using this opcode for
>> anonymous transactions.
>
> I believe I understand what the opcode does directly— it just
> validates an opaque signautre. I don't understand how it enables
> anonymous transactions.
>
> Can you spell this out for me?
One doesn't use this opcode as the sole thing to secure a transaction.
Instead this opcode prevents double spend attacks against
anonymization schemes. The idea is for Alice to give signatures to the
recipients of funds, all signatures being equivalent. To avoid this
from leading to a double-spend, we use a quorum method based on
showing earlier redemptions happened.
>
> In particular I don't see why it is not, from the perspective of the
> blockchain, isomorphic to a hash locked transaction. Â (This
> equivalence is more obvious when you think about how lamport
> signtures turn simple hashing into a one time signature).
Because you can't blind a lamport signature, it isn't. I'm searching
for a place to post the current draft: it's not ready for anything
official yet, but does seem to be of interest. Drop me a (offlist)line
if you have ideas about where I can put it.
Sincerely,
Watson Ladd
--
"Those who would give up Essential Liberty to purchase a little
Temporary Safety deserve neither Liberty nor Safety."
-- Benjamin Franklin
Watson Ladd [ARCHIVE] /
npub108…sr4hp
2023-06-07 03:11:26
in reply to nevent1q…4wh7
Author Public Key
npub108dfgewsuqzm6cvllzmxsv0xnn69rrjnyg5pa32a727k89ndh3xqmsr4hpPublished at
2023-06-07 03:11:26Event JSON
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"content": "📅 Original date posted:2012-03-06\n📝 Original message:On Tue, Mar 6, 2012 at 6:05 PM, Gregory Maxwell \u003cgmaxwell at gmail.com\u003e wrote:\n\u003e On Fri, Mar 2, 2012 at 2:57 PM, Watson Ladd \u003cwbl at uchicago.edu\u003e wrote:\n\u003e\u003e I am proposing a new opcode for the purposes of anonymous\n\u003e\u003e transactions. This new opcode enables scripts to be given proof that\n\u003e\u003e the receiver can carry out or has carried out a previous transaction.\n\u003e\u003e I'm currently working on a paper that discusses using this opcode for\n\u003e\u003e anonymous transactions.\n\u003e\n\u003e I believe I understand what the opcode does directly— it just\n\u003e validates an opaque signautre. I don't understand how it enables\n\u003e anonymous transactions.\n\u003e\n\u003e Can you spell this out for me?\nOne doesn't use this opcode as the sole thing to secure a transaction.\nInstead this opcode prevents double spend attacks against\nanonymization schemes. The idea is for Alice to give signatures to the\nrecipients of funds, all signatures being equivalent. To avoid this\nfrom leading to a double-spend, we use a quorum method based on\nshowing earlier redemptions happened.\n\u003e\n\u003e In particular I don't see why it is not, from the perspective of the\n\u003e blockchain, isomorphic to a hash locked transaction.  (This\n\u003e equivalence is more obvious when you think about how lamport\n\u003e signtures turn simple hashing into a one time signature).\nBecause you can't blind a lamport signature, it isn't. I'm searching\nfor a place to post the current draft: it's not ready for anything\nofficial yet, but does seem to be of interest. Drop me a (offlist)line\nif you have ideas about where I can put it.\nSincerely,\nWatson Ladd\n\n-- \n\"Those who would give up Essential Liberty to purchase a little\nTemporary Safety deserve neither Liberty nor Safety.\"\n-- Benjamin Franklin",
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