<p>Full nodes derive their security from enforcing all of the rules of Bitcoin self-sufficiently on any data they receive, and by validating the complete blockchain from the genesis block to the chain tip. This does not require keeping the data after validating it. Pruning nodes have the same security that archival nodes have. Since following Bitcoin's rules is sufficient to converge to the chain-tip, pruning nodes have full consensus capability.</p>
<p>The only difference is that pruning nodes cannot serve the blocks that they have pruned, and if a pruning node requires a <code>-reindex</code> for any reason, it will need to repeat the full Initial Block Download (IBD).</p>

CC BY-SA 4.0
2021-05-11T18:52:58.150Z
"they cannot serve the blocks that they have pruned".
Is this a security issue if most nodes are pruning?
Vizeet Srivastava
CC BY-SA 4.0
2021-05-12T17:09:24.953Z
No, it would simply mean that the data is harder to get, but since any provided data would still be protected by the hash, it could not be faked either.
Murch
CC BY-SA 4.0
2017-03-05T20:25:32.887Z
2021-05-12T19:13:10.353Z
2021-05-12T19:13:10.353Z
Murch
<p>An SPV node certainly is a compromise of security because the full set of consensus rules are not verified by the node (for example block size or subsidy rules). A pruned node seems like a win-win, except you can't help new nodes bootstrap on to the network. </p>

<p>Are there any other tradeoffs?</p>

<security><consensus><full-node><pruning>
Does pruning affect a node's security or consensus ability?
pinhead
# Does pruning affect a node's security or consensus ability?

(Asked by: username_0 on 2017-03-05)

An SPV node certainly is a compromise of security because the full set of consensus rules are not verified by the node (for example block size or subsidy rules). A pruned node seems like a win-win, except you can't help new nodes bootstrap on to the network.

Are there any other tradeoffs?

**Tags:** security, consensus, full-node, pruning


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## 1 answers

### Answer by username_1 on 2017-03-05. Score: 2 | Accepted answer

Full nodes derive their security from enforcing all of the rules of Bitcoin self-sufficiently on any data they receive, and by validating the complete blockchain from the genesis block to the chain tip. This does not require keeping the data after validating it. Pruning nodes have the same security that archival nodes have. Since following Bitcoin's rules is sufficient to converge to the chain-tip, pruning nodes have full consensus capability.

The only difference is that pruning nodes cannot serve the blocks that they have pruned, and if a pruning node requires a `-reindex` for any reason, it will need to repeat the full Initial Block Download (IBD).

> **Comments:**
> **username_2**: "they cannot serve the blocks that they have pruned". Is this a security issue if most nodes are pruning?  
> **username_1**: No, it would simply mean that the data is harder to get, but since any provided data would still be protected by the hash, it could not be faked either.  

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