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0 pointslalaland11258y ago0 comments

See section 9.5 of the lightning whitepaper:

> 9.5 Forgetting to Broadcast the Transaction in Time

> If one does not broadcast a transaction at the correct time, the counterparty may steal funds.

You need to be online all the time (or at least frequently enough) so that you can publish a penalty transaction if your counter party tries to steal coins from you.

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gruez8y ago

This can be easily be solved by pre-signing that transaction and having a third party service broadcast that transaction if you're not online.

throwaway20488y ago

if you have to trust third parties, whats the point?

gruez8y ago

you don't. you're not handing over the private keys. you sign the transaction locally, and give them to the third party to broadcast in case you're not online. it can even be multiple third parties so you're not trusting a single one. this provides better reliability than broadcasting it yourself on your home/vps/colo connection.

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binarybits8y ago

I see what you mean. Three thoughts on this:

* The time lock on commitment transactions is typically set to be a few days, so you don't need to be online "constantly." At most you need to check in about once a day.

* As the white paper says, you can delegate this function to a third party, without giving the third party the ability to steal your funds.

* If the other party tries to steal your funds and you catch him, you get to steal all of his funds. So in practice I don't expect this to be a common situation. If the other guy believes there's at least a 90 percent chance that you'll check the blockchain on any given day, then the expected value of broadcasting a revoked transaction is going to be heavily negative.

lalaland1125OP8y ago

One interesting comment about the third point is that once a channel gets sufficiently depleted (say down to 10% of the balance on one side), then there is an increased incentive to cheat (because the potential losses are lower). So you will usually have to keep channels at above a certain balance for security reasons.

freejulian8y ago

Sure, but there’s services you can outsource that to. Furthermore, if you only use lightning for sending payments (the majority of us) then publishing an earlier version of the channel benefits you!

philipwhiuk8y ago

Are those services called banks?

Klathmon8y ago

You could call them that if you want, but they are significantly different than traditional banks.

These services won't actually hold your money, just a transaction that sends all the money to you if someone tries to cheat. It's more of an escrow service than a bank, but the escrow service again doesn't actually hold anything valuable.

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gruez8y ago

This can be easily be solved by pre-signing that transaction and having a third party service broadcast that transaction if you're not online.

throwaway20488y ago

if you have to trust third parties, whats the point?

gruez8y ago

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binarybits8y ago

I see what you mean. Three thoughts on this:

* The time lock on commitment transactions is typically set to be a few days, so you don't need to be online "constantly." At most you need to check in about once a day.

* As the white paper says, you can delegate this function to a third party, without giving the third party the ability to steal your funds.

lalaland1125OP8y ago

freejulian8y ago

philipwhiuk8y ago

Are those services called banks?

Klathmon8y ago

You could call them that if you want, but they are significantly different than traditional banks.

1 more reply

j / k navigate · click thread line to collapse