rich1.0npub1r375vdaydp5nnnytff6ee2kwzxak8whmwkmnkm6h67agr7dadfkqxn6ccqhttps://nostr.ae/npub1r375vdaydp5nnnytff6ee2kwzxak8whmwkmnkm6h67agr7dadfkqxn6ccqnjumphttps://nostr.ae📅 Original date posted:2017-12-27 📝 Original message: Andy Schroder On 12/27/2017 01:06 AM, ZmnSCPxj wrote: > Good morning Andy, > >> Andy Schroder >> On 12/27/2017 12:18 AM, Andy Schroder wrote: >>>> Channel closing >>>> costs dwarf the gains to be made from cheating, however. >>>> >>>> >>>>> Since millisatoshis is used, is there a maximum channel funding size? >>>> Yes, the upper 32 bits must be zero, from BOLT #2: >>>> >>>> - for channels with `chain_hash` identifying the Bitcoin >>>> blockchain: >>>> - MUST set the four most significant bytes of `amount_msat` to 0. >>>> >>>> This gives a maximum HTLC value of .04294967295 BTC, which, back when >>>> we started, was about $10. >>>> >>> >>> What's the point of wasting the upper 32 bits? Seems like this is a >>> waste of data? >>> >>> If you have the lower 32 bits of data to use, and >>> 2^32=4,294,967,296, then you have 4,294,967,296 milli satoshis. 1 >>> BTC=10^11 milli satoshis, so 4,294,967,296 milli satoshis/((10^11 >>> milli satoshis)/1BTC) = 0.04294967296 BTC. That is off by 1 milli >>> satoshi from what you say above. Why is this? >>> >>> Regardless of the discrepancy of 1 milli satoshi, it still seems >>> like 0.04294967296 BTC is kind of a low maximum channel size for a >>> lot of business applications. Why do you want to limit this when you >>> have those extra 4 bytes set to zero? You think any more is too much >>> to safely have in a hot wallet? You felt keeping it low will >>> encourage decentralization? Something else? >>> > > Yes, I believe Rusty did indeed consider 42mBTC as a reasonable amount > to transfer on Lightning. So that in case of trouble on Lightning, > not a lot of money gets lost. At the time he decided this 42mBTC > limit, it was about 10 USD only, so Rusty could always just buy you a > drink if he somehow causes c-lightning to lose that much. > > Of course, 42mBTC today is much larger. > > For myself, I think the channel limit of 167mBTC is good as it > encourages decentralization by encouraging people to make many small > channels than one large channel. Many small channels helps in keeping > your funds resilient against temporary outages of your fellow nodes. I understand what you are saying about decentralization, but is this really something that will be enforceable? Seems like people will just make an alt-lightning network layer with different limits to get around this, since there isn't really a consensus rule set like on the block chain to motivate them. > >>> >>> Is the max HTLC value the same as the maximum channel size? >> >> Okay, so I may have discovered part of this answer to this question >> in BOLT 2 where it says: "MUST set|funding_satoshis| to less than >> 2^24 satoshi". However, I still don't understand the rational of why >> |max ||funding_satoshis doesn't equal max |amount_msat, or where the >> values of (2^24)*10^3 and 2^32 milli satoshis came from. Also, why >> don't you use units of millisatoshis everywhere in the spec? >> Sometimes it's satoshis and sometimes it's milli satoshis. >> > > This is actually very simple. Everything that touches the chain > (opening and closing) uses satoshis. Everything that does not, uses > millisatoshis. This is because the chain uses satoshis as the > smallest amount. Offchain, we can use millisatoshis, and it is used > everywhere offchain. Okay, the unit choices now make sense! > > Regards, > ZmnSCPxj > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.linuxfoundation.org/pipermail/lightning-dev/attachments/20171227/51e762f0/attachment-0001.html>