Date: Mon, 05 Oct 2020 02:41:14 +0000
To: ZmnSCPxj <ZmnSCPxj@protonmail.com>,
 Bitcoin Protocol Discussion <bitcoin-dev@lists.linuxfoundation.org>
From: ZmnSCPxj <ZmnSCPxj@protonmail.com>
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Subject: Re: [bitcoin-dev] A thought experiment on bitcoin for payroll
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Good morning Mr. Lee,


> Permanent raises can justify permanently increasing the size of the chann=
el with the employee.

On reflection, this is a bad idea.

Suppose I am a cut-throat employee and I want to have an idea of the bi-wee=
kly salary of another employee.

I make some stupid bet, and lose, with the other employee.
I offer to pay the loss of my bet via Lightning, and the other employee, in=
 all innocence, issues a Lightning invoice to me.

The Lightning invoice contains the actual node ID of the other employee.
And since I also have a channel with the cut-throat company, I know as well=
 the node ID of the cut-throat company.

I can then look at the gossiped channels and see the size of the channel be=
tween the cut-throat company and the other employee, and from there, guess =
that this is the bi-weekly salary of that employee.

On the other hand --- once the employee has *any* funds at all, they can si=
milarly take an offchain-to-onchain swap, and then use the funds to create =
another channel to another part of the network.
The other employee as well can arrange incoming funds on that other channel=
 by using offchain-to-onchain swaps to their cold storage.
Thus, as an employee gets promoted and pulls a larger bi-weekly salary, the=
 channel with the cut-throat company becomes less and less an indicator of =
their *actual* bi-weekly salary, and there is still some deniability on the=
 exact size of the salary.

At the same time, even if I know the node of the other employee, the size o=
f all its channels is also still not a very accurate indicator of their sal=
ary at the throat-cutting company.
For example, it could be a family node, and the other employee and all her =
or his spouses arrange to have their salaries paid to that node.
Or the other employee can also run a neck-reconstruction business on the si=
de, and also use the same node.
(Nodelets for the win?)

Regards,
ZmnSCPxj