From the main article, I2P has 55,000 computers, the botnet tried to add 700,000 infected routers to I2P to use it as a backup command-and-control system.
https://news.ycombinator.com/item?id=46976825
This, predictably, broke I2P.
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That's an interesting stress test for I2P. They should try to fix that, the protocol should be resilient to such an event. Even if there are 10x more bad nodes than good nodes (assuming they were noncompliant I2P actors based on that thread) the good nodes should still be able to find each other and continue working. To be fair spam will always be a thorny problem in completely decentralized protocols.
> Even if there are 10x more bad nodes than good nodes [...] the good nodes should still be able to find each other
What network, distributed or decentralized, can survive such an event? Most of the protocols break down once you hit some N% threshold of the network being bad nodes, asking it to survive 1000%+ bad nodes when others usually is something like "When at least half the nodes are good". Are there existing decentralized/distributed protocols that would survive a 1000% attack of bad nodes?
No. They should not try to survive such attacks. The best defense to a temporary attack is often to pull the plug. Better than than potentially expose users. When there are 10x as many bad nodes as good, the base protection of any anonymity network is likely compromised. Shut down, survive, and return once the attacker has moved on.
This is why Tor is centralized, so that they can take action like cutting out malicious nodes if needed. It’s decentralized in the sense that anyone can participate by default.
> so that they can take action like cutting out malicious nodes if needed
How does that work?
While anyone can run a Tor node and register it as available, the tags that Tor relays get assigned and the list of relays is controlled by 9 consensus servers[1] that are run by different members the Tor project (in different countries). They can thus easily block nodes.
Interesting, thank you so much! Yeah, if those 9 really are independent entities, I’d say I don’t see many issues here.
It's 10, not 9. And there are severe problems with having a total of 10 DA be the essential source of truth for whole network. It would be trivial to DDoS the DAs and bring down the Tor network or at the very least, disrupt it: https://arxiv.org/abs/2509.10755.
It's the only complaint I have of the current state of Tor. Anyone should be able to run directory authority, regardless if you trust the operator or not (same as normal relays).
Couldn't you
A: Run your own network that trusts the existing plus whatever nodes you think ought to be and convince everyone that this is better if it is
B: Run a node and convince others to trust yours so that eventually there is 11 then 12 and so forth?
Anyone can. The DA code is open source and is used whenever you run a testnet. You can also run a DA on the mainnet - how do you think the 10 primary DAs exist? They're not 10 computers owned by a single organization - they're 10 mutually trusting individuals. However, most of the network won't trust you.
Why would an attacker move on if it can maintain a successful DoS attack forever?
Because botnets are mostly there to make money nowadays. Or owned by state actors.
Either way, it’s opportunity cost.
The mentioned botnet didn't intentionally take down I2P. It's run by bunch of kids who don't know what they're doing.
Finding good nodes is a thorny problem for human friendship, too!
That's why the Web of Trust, or classic GNUPG key signing parties are a forgotten/ignored must have. Anyone can change and go rouge of course, but it's statistically less likely.
If I understand gp correctly, the web of trust comes after finding these human nodes, and will not help you in the process.
It doesn't work for I2P due to its design, but for things like Nostr, it works well. Essentially, the goal is to build up a list of "known" reliable relays over time, while simultaneously blacklisting anyone who joins and proves to be unreliable relying on the statistic that collaborative individuals outnumber hostile ones in any sufficiently large cohort.
Of course, it's far from being 100% effective, but it mitigates the issue significantly.
Hostile entities generally have a lot of money they can use to perform a Sybil attack.
Sure, but can't break the trusted part of the network who can remain operational in that case, even if not really anonymous anymore.
Funny and excellent comment!
I guess "predictably" is valid but what actually went wrong? After going through multiple sources I can't tell if the botnet nodes were breaking the protocol on purpose, breaking the protocol on accident, or correct implementations that nevertheless overwhelmed something.
As I understand they weren't building tunnels, so every time a legit client wanted to it has to wade through all the bad nodes to find a good one, so everything slowed right down. I was building at about 3% success rate during the issue which enables general eepsite browsing but torrenting was essentially dead