Does running a node benefit the network?

Question

There is a 10-year old question asking this. The sole answer to that question at the time was essentially a yes, and I've seen people say that running a node makes the network more "secure" and "decentralized". However, I've also seen prominent Bitcoin developers [1][2] say that a full node that isn't actually used by its user to verify the chain is basically useless. So how is it really?

To expand on the original question, assuming some nodes do actually contribute to the network, not all nodes obviously contribute the same. I would like to know how some factors might play into this:

• running a pruned vs unpruned node
• running over clearnet, Tor or both
• whether incoming connections are allowed
• available bandwidth and hardware

Answer 1

I don't think I'm qualified to give a full answer, but I do think a full node which doesn't actually have an "economically active user" behind it could still be a benefit to the network.

The Bitcoin wiki says:

Myth: I can just set up a node on a cloud server instance and leave it

To get the benefits of running a full node, you must use it as your wallet, preferably on hardware you control.

Most people who do this do not use a full node as their wallet. Unfortunately because Bitcoin has a similar name to Bittorrent, some people believe that upload capacity is the most important thing for a healthy network. As I've explained above: bandwidth and connections are not a problem today; trust, security and privacy are.

I read Jameson Lopp's recent article "Is the Bitcoin Network slowing down?" which suggests that initial block download speeds could be affected by the restricted upload bandwidth of many full nodes, particularly those on asymmetric residential connections:

Finally, there's a question of actual bandwidth. Per Marco Falke's original suggestion, there could just be a lot of slow or even malicious peers on the network that deliver block data slowly or not at all.

So I think an otherwise "unused" node sitting on a cloud server or other high-bandwidth connection which is willing to serve historical blocks is probably performing a useful service for the network these days.