<p>Just to expand a little bit the answer is already given.</p>
<p>Zero-conf channels, also called turbo channels, are new single-funded channels where the funder gives some or all of their initial funds to the acceptor. Those funds are not secure until the channel open transaction receives a sufficient number of confirmations, so there’s no risk to the acceptor spending some of those funds back through the funder using the standard LN protocol.</p>
<p>For example, Alice has several BTC in an account at Bob’s custodial exchange. Alice asks Bob to open a new channel paying her 1.0 BTC. Because Bob trusts himself not to double-spend the channel he just opened, he can allow Alice to send 0.1 BTC through his node to third-party Carol even before the channel open transaction has received a single confirmation.</p>
<p><img src="https://bitcoinops.org/img/posts/2021-07-zeroconf-channels.png" alt="" /></p>
<p>See more here: <a href="https://bitcoinops.org/en/topics/zero-conf-channels/" rel="nofollow noreferrer">https://bitcoinops.org/en/topics/zero-conf-channels/</a>
See the BOLT RFC here: <a href="https://github.com/lightning/bolts/pull/910" rel="nofollow noreferrer">https://github.com/lightning/bolts/pull/910</a></p>
<p>ofcs you are trusting the other side so in case of fee spike there are problems</p>

CC BY-SA 4.0
2023-08-13T09:59:57.867Z
2023-08-13T09:59:57.867Z
vincenzopalazzo
<p>You can have a trustless zero-confirmation channel if it's funded from a 2-of-2 multisignature address and each party has one of the private keys. As far as I can tell, any other setup requires trusting the other party that they don't try to double-spend. Other than that, it works just like a normal channel.</p>

CC BY-SA 4.0
2021-07-23T17:20:38.410Z
Except this model is susceptible to fee based attacks like cpfp based tx pinning
arshbot
CC BY-SA 4.0
2022-09-28T14:43:24.007Z
Stumbled upon this question while searching something else. A wiser arshbot knows that cpfp carve out solves this concern.
arshbot
CC BY-SA 4.0
2021-07-23T12:05:50.863Z
2021-07-23T12:05:50.863Z
Vojtěch Strnad
<p>What zero-conf channels are seems pretty straighforward (correct me if I'm wrong) -- channels that are immediately usable without needed confirmation on the blockchain. These are very useful since Alice can get Bob set up on Lightning without needed to wait for confirmation.</p>
<p>If there are different variants, can you describe how each works,trust assumptions, and possible drawbacks/attack vectors?</p>

<lightning-network><trust><ln-opening-channels>
How do zero-conf channels work?
arshbot
# How do zero-conf channels work?

(Asked by: username_0 on 2021-07-23)

What zero-conf channels are seems pretty straighforward (correct me if I'm wrong) -- channels that are immediately usable without needed confirmation on the blockchain. These are very useful since Alice can get Bob set up on Lightning without needed to wait for confirmation.

If there are different variants, can you describe how each works,trust assumptions, and possible drawbacks/attack vectors?

**Tags:** lightning-network, trust, ln-opening-channels


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## 2 answers

### Answer by username_1 on 2023-08-13. Score: 0 | Accepted answer

Just to expand a little bit the answer is already given.

Zero-conf channels, also called turbo channels, are new single-funded channels where the funder gives some or all of their initial funds to the acceptor. Those funds are not secure until the channel open transaction receives a sufficient number of confirmations, so there’s no risk to the acceptor spending some of those funds back through the funder using the standard LN protocol.

For example, Alice has several BTC in an account at Bob’s custodial exchange. Alice asks Bob to open a new channel paying her 1.0 BTC. Because Bob trusts himself not to double-spend the channel he just opened, he can allow Alice to send 0.1 BTC through his node to third-party Carol even before the channel open transaction has received a single confirmation.

![](https://bitcoinops.org/img/posts/2021-07-zeroconf-channels.png)

See more here: <https://bitcoinops.org/en/topics/zero-conf-channels/>
See the BOLT RFC here: <https://github.com/lightning/bolts/pull/910>

ofcs you are trusting the other side so in case of fee spike there are problems


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### Answer by username_2 on 2021-07-23. Score: 0

You can have a trustless zero-confirmation channel if it's funded from a 2-of-2 multisignature address and each party has one of the private keys. As far as I can tell, any other setup requires trusting the other party that they don't try to double-spend. Other than that, it works just like a normal channel.

> **Comments:**
> **username_0**: Except this model is susceptible to fee based attacks like cpfp based tx pinning  
> **username_0**: Stumbled upon this question while searching something else. A wiser username_0 knows that cpfp carve out solves this concern.  

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