<p>483 because the commitment transaction might otherwise become too large if it hits the chain.</p>
<p>Ramifications are:</p>
<ul>
<li>blackmail fee attacks (c. F. <a href="https://lists.linuxfoundation.org/pipermail/lightning-dev/2020-June/002735.html" rel="nofollow noreferrer">https://lists.linuxfoundation.org/pipermail/lightning-dev/2020-June/002735.html</a> a similar attack is known as  flood  and loot)</li>
<li>possible congestion of channels (right now only if conducted by an attacker but later potentially due to payment delivery and high routing demand on channels.)</li>
</ul>
<p>To mitigate those attacks currently most nodes have 30 htlcs as a default value.</p>

CC BY-SA 4.0
2021-08-12T18:11:26.427Z
2021-08-12T18:11:26.427Z
Rene Pickhardt
<p>Channels can have pending HTLCs, or even handle multiple payments concurrently. Is there a max number of pending HTLCs a channel can entertain? What is that max, why is it set to that number, and what are potential ramifications of a higher value (is latency a concern?)</p>

CC BY-SA 4.0
2021-09-21T17:31:05.563Z
related: https://bitcoin.stackexchange.com/questions/93720/lightning-network-how-was-the-maximum-allowed-htlcs-in-flight-computed
arshbot
<lightning-network><hash-time-locked-contract><channels>
how many htlcs can a lightning channel have pending at a given time
arshbot
# how many htlcs can a lightning channel have pending at a given time

(Asked by: username_0 on 2021-08-12)

Channels can have pending HTLCs, or even handle multiple payments concurrently. Is there a max number of pending HTLCs a channel can entertain? What is that max, why is it set to that number, and what are potential ramifications of a higher value (is latency a concern?)

**Tags:** lightning-network, hash-time-locked-contract, channels

> **Comments:**
> **username_0**: related: https://bitcoin.stackexchange.com/questions/93720/lightning-network-how-was-the-maximum-allowed-htlcs-in-flight-computed  

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## 1 answers

### Answer by username_1 on 2021-08-12. Score: 1 | Accepted answer

483 because the commitment transaction might otherwise become too large if it hits the chain.

Ramifications are:

* blackmail fee attacks (c. F. <https://lists.linuxfoundation.org/pipermail/lightning-dev/2020-June/002735.html> a similar attack is known as flood and loot)
* possible congestion of channels (right now only if conducted by an attacker but later potentially due to payment delivery and high routing demand on channels.)

To mitigate those attacks currently most nodes have 30 htlcs as a default value.


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