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I am building a bitcoin lightning network using lnd on a separate computer
this computer has less than 200G avaible and the actual blockchain is more than 220G, so I am gonna need to use prude mod and began the download of the chain starting from march 2018 as recquired by lnd,
my question is which bitcoin client is able to do that and how to configure it for this procedure ?
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The keyword you are probably looking for is neutrino as explained in the article by lightning labs.
From the conclusion of the article I quote:
We’re excited to have released the first implementation of BIP 157/158-compliant Neutrino clients in lnd 0.5 and in the Lightning App alpha. While these initial releases are for testnet, mainnet Neutrino is in progress as well. Note also that Neutrino serving support has been added to btcd, and support for BIP 158 has been merged into bitcoind (Bitcoin Core). [...] While support for BIP 158 has been merged into bitcoind, support for BIP 157 has not yet been merged, so Neutrino filters can’t yet be served by bitcoind full nodes.
So I guess that currently you will need to run btcd together with lnd. The configuration can probably taken from the README of https://github.com/lightninglabs/lightning-app
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I am gonna need to use prude mod and began the download of the chain starting from march 2018 as recquired by lnd,
my question is which bitcoin client is able to do that and how to configure it for this procedure ?
I don’t believe any client can do this: how will your node know if a UTXO from before March 2018 was valid if it hast verified the full history of the chain?
When a node is bootstrapped, it will work through the blockchain’s history to build a UTXO set. Without being able to build and verify this UTXO set from scratch, there is no way to know that a UTXO is valid (without trusting someone else). For example, if someone opened a channel with your node, by consuming a UTXO from 2017, how would your node be able to determine the validity of that UTXO?
Even for a neutrino-serving node like btcd, the node still needs to have verified the entire history, in order to serve the LN node valid data.
Maybe that should be a different question but I guess the same holds true for accumulators like utreexo? – Rene Pickhardt – 2019-07-13T19:48:00.443
@RenePickhardt Good question. I’ve seen a few proposals for ways to add UTXO commitments to Bitcoin, and I believe they could provide a mechanism for achieving what OP desires (though they are not yet implemented at this point, and there are some security implications: instead of just trusting the math and code your node is running to do these checks, you must trust others (in aggregate) to do them, and you must trust the method of aggregation (more math, more code) to be secure as well). – chytrik – 2019-07-13T20:01:12.853
decided to extract the discussion to a separate question for better indexability: https://bitcoin.stackexchange.com/questions/89023/what-are-the-downsides-of-integrating-accumulators-like-utreexo-to-bitcoind
– Rene Pickhardt – 2019-07-13T21:25:15.073