The next release of Electrum will support Lightning payments

[hugeblack]

This news is amazing. Here are some quick answers:

 - Written in python? Yes
 - Does it need to run a lightning node? You won't need to run anything else.
 - Non-custodial (Not your keys, Not your coins)

The source of the answers above is @ElectrumWallet Twitter account

The next release of Electrum will support Lightning payments. Our lightning node implementation has been merged into Electrum's master branch.

No deadline has been set for launching the update, but I am sure I will update my wallet as soon as it is released. "I may wait several days to confirm the comments of members."

[jackg]

I think they've been working on trying to support the lightning network for at least half a year so it's great to see they've got something going there!

Does it need the server to run (have you checked the merged source yet) or will they host the nodes from the electrum client software?

[Rath_]

Does it need the server to run (have you checked the merged source yet) or will they host the nodes from the electrum client software?

No additional software is needed; a light node is run locally. Electrum will act similarly to Eclair Mobile and other non-custodial mobile wallets. Users will need to be online in order to receive payments and take care of the backups. Channels are probably going to be marked as private ones so earning money from payment routing is out of the question. Take a look at this short presentation.

[DireWolfM14]

Awesome news, I'm anxiously awaiting this new toy opportunity to lean more about lightning.  Electrum implementing lightning functionality is likely to be a big boost for the technology.  So many people use electrum, but may have never researched how it works or how to use it.

Just fair warning to anyone who's going to jump in head first: This is still new, experimental technology, don't put more money into a lighting channel than you are willing to lose.

[o_e_l_e_o]

In addition to the points above:

Electrum will be a lightning node. You won't need to run anything else.

Thomas V gave a presentation on Lightning and Electrum a few months ago, you can see the slides here: https://www.electrum.org/talks/lightning/presentation.html. Seems to suggest that users will initially be required to run their own watchtowers?

Channels are probably going to be marked as private ones so earning money from payment routing is out of the question.

What makes you say that? If you are staying online 24/7 (or close to it), is there any reason you couldn't be a public channel?

[Rath_]

If you are staying online 24/7 (or close to it), is there any reason you couldn't be a public channel?

Yes, there are a few reasons. Anyone will be able to see the channel using the Lightning Network explorers - it might bother some people. Also, public channels are forced to participate in payment routing. This could confuse people using the Lightning Network for the first time. One can change the fee policy to discourage others from routing through one's node but that would require more work from the developers to make it more newbie friendly.

[pooya87]

does anybody know if Electrum with -testnet command would also support Lightning Network in this new release?
i would very much prefer to test things on testnet with value-less coins to get comfortable using LN through Electrum. specially since my knowledge of LN is pretty much minimal.

[d5000]

does anybody know if Electrum with -testnet command would also support Lightning Network in this new release?
i would very much prefer to test things on testnet with value-less coins to get comfortable using LN through Electrum. specially since my knowledge of LN is pretty much minimal.

I guess yes - at least regtest already works with the development version. Electrum dev Thomas Voegtlin - already in June - has given a little explanation talk/video and a presentation about how a LN channel can be tested without having to connect to the "real" network and risk coins.

Video: https://www.youtube.com/watch?v=7D83IpdiF-U
Presentation: https://www.electrum.org/talks/lightning/presentation.html#slide1

(Edit: I see o_e_l_e_o already linked to the presentation before.)

Basically, you simply create two different nodes on your PC and then connect them via LND and build a channel between them. However, I guess it's also possible to test it with the "main" testnet.

I have tried the newest Electrum master version. (Obviously, everybody doing that should create a new wallet for it!) There is no longer a need to specify the "--lightning" command line option when starting electrum to enable the LN functionality. However, you have to activate it inside the wallet.

The way I did it was via the console: entering "init_lightning()" creates the needed Lightning keys. Then it's necessary to restart the client and the LN functionality is activated (one can create channels, etc.).

Does anybody know if there is a better way than via init_lightning(), i.e. is it possible with a GUI function?

[bitmover]

Does it need the server to run (have you checked the merged source yet) or will they host the nodes from the electrum client software?

No additional software is needed; a light node is run locally. Electrum will act similarly to Eclair Mobile and other non-custodial mobile wallets. Users will need to be online in order to receive payments and take care of the backups. Channels are probably going to be marked as private ones so earning money from payment routing is out of the question. Take a look at this short presentation.

i hope it is better than Eclair. =D
I paid so much in fees to open/close channels there, because there was not too many customization options.

I am happy to finally have a decent lightning wallet. Maybe this will trigger more adoption.

[Rath_]

I found a little interesting information on the Electrum's GitHub page. Some of them might have changed since the message was posted on 14th November 2018. As I predicted in my previous message, Electrum nodes won't be able to participate in payment routing and their channels will be marked as private. Electrum Technologies GmbH is going to run their own watchtower which every user will be able to use for a flat monthly fee.

[Rath_]

Someone published a video on YouTube showcasing the preview version of Electrum with the Lightning Network support. It doesn't look complicated at all but it would be nice if a detailed explanation was presented whilst hovering the mouse over the 'Push amount'. It might not be obvious for everyone.

[jackg]

@bitcyptex, he seems to think push is receivable amount (I think) it's good that you can customise it as you normally can't on the mobile wallets.

Also I think his transaction failed because he was trying to send testnet bitcoins to a lightning bitcoin node (just thought I'd make this clear if anyone was wondering).

[Rath_]

@bitcyptex, he seems to think push is receivable amount (I think) it's good that you can customise it as you normally can't on the mobile wallets.

Well, he is not completely wrong. He is now able to receive coins over the Lightining Network. However, the other party can spend the coins which were pushed to them. This feature can be also useful in some other ways.

Also I think his transaction failed because he was trying to send testnet bitcoins to a lightning bitcoin node (just thought I'd make this clear if anyone was wondering).

That's not it. The website he used generates invoices for the testnet. Take a look at the following piece of code.

Code: (https://github.com/spesmilo/electrum/blob/0966edc637ba927ea6767b44aa937b0ca7805dd7/electrum/lnpeer.py)

if htlc.cltv_expiry - lnutil.NBLOCK_DEADLINE_BEFORE_EXPIRY_FOR_RECEIVED_HTLCS <= local_height \
                or next_cltv_expiry <= local_height:
            reason = OnionRoutingFailureMessage(code=OnionFailureCode.EXPIRY_TOO_SOON,
                                                data=outgoing_chan_upd_len+outgoing_chan_upd)
            await self.fail_htlc(chan, htlc.htlc_id, onion_packet, reason)
            return

htlc.cltv_expiry seems to be the culprit here. If you compare the 'Time Lock Delta' for both testnet and mainnet on 1ml.com, you will see that it is equal to 40 and 144 respectively. At the time of the recording, the blocks on the testnet were mined one after another. If you take both of these factors in the account then it seems that that's the reason why it didn't work. It's a bit late here so I will investigate it further tomorrow.

Note: It seems that some mainnet notes have set their 'Time Lock Delta' to 40 or lower. The blocks on the mainnet are mined not as fast as on the testnet so it shouldn't impact the mainnet Lightning Network transaction failure rate significantly.

The time_lock_delta is the minimum difference in the number of blocks between the CLTV of an incoming HTLC and the forwarded HTLC.

I would appreciate if someone could link this post under that YouTube video.