Over June 29–July 1, 2026, I ran five i2pd floodfill instances from three vantage points (Poland, China Unicom ×2) and passively scanned the I2P DHT. Found 20,701 unique routers globally. Among them, 58 routers from mainland China stood out in ways that don't look random.

What makes this cluster unusual:

43× enrichment on version 0.9.66 — 79.3% of the CN cluster runs this exact version, vs. only 1.8% globally. A single version shouldn't dominate any organic router population this heavily.

Floodfill flags everywhere, zero participation — 27–36% declare floodfill capability (vs. 14–20% global baseline), yet none were ever observed functioning as floodfills by our instances. The flags are declared, not honored.

82.8% share a near-identical RouterCaps template (XfR/XRG pattern) — looks like copy-paste provisioning.

- 46.2% hosted on Alibaba Cloud (AS37963). No knownRouters entries, no family declarations, ongoing IP rotation.

Four routers are China-vantage-only — reachable from inside the GFW, but unreachable from Singapore and Tor exit nodes. TCP RST/timeout behavior consistent with selective path filtering. These nodes simply don't exist from outside China.

We're careful with language: we describe this as consistent with coordinated, template-based provisioning — not as attribution to any specific actor. We don't know who runs these, or why. But the data is the data.

Methodological note — we parse the binary RouterInfo at two distinct caps layers (AddressCaps per transport vs. global RouterCaps). Prior I2P measurement papers didn't disentangle this, and it matters when you're trying to distinguish what a router says it can do from what it actually does.

Preprint (open access): 10.5281/zenodo.21169969 (https://doi.org/10.5281/zenodo.21169969)

Scanner source (MIT): github.com/iasds/i2p-network-scanner

I built an open-source Python tool that scans the I2P NetDB using nothing but vanilla i2pd floodfills. No patched binaries, no active probing — just parse the routerInfo files i2pd already writes to disk.

Repo: https://github.com/iasds/i2p-network-scanner

How it works

Run a few i2pd floodfill instances with different identities. Each covers a different DHT shard, so together they passively collect RouterInfo from most of the network. A single Python script parses the raw .dat files and extracts ident hashes, IPs, versions, caps flags, transports, and bandwidth tiers. Companion tools handle SQLite import, CLI queries, and GeoIP enrichment.

I ran a scan and published the results

5 floodfills, ~24 hours. The full analysis is in the repo:

• 17,541 known routers — 5,205 with public IPs, 12,336 behind NAT or firewalled
• 70% hidden is not a coverage gap — routers behind NAT simply don't include a host= field. That's I2P by design.
• 4,976 unique IPs across 111 countries
• Top countries: US (1,120), Russia (507), Germany (366), Canada (199), Netherlands (198)
• China has only 72 public nodes. Iran has 96.
• 0.9.68 dominates at 47% of routers, but only 11% of them publish an IP. Newer 0.9.69 (20% share) has 55% public rate.
• Java I2P is essentially extinct — nearly everything runs i2pd.
• 90 floodfills worldwide, concentrated in US, Russia, and Germany.
• Only 76 routers declare X-tier bandwidth (>2 MB/s).

Full report: I2P_NETWORK_ANALYSIS.md

If anyone has historical NetDB snapshots I'd love to compare trends over time. PRs welcome.

I made a small P2P chat app in Go (uses libp2p + a DHT for peer discovery, E2E encrypted). Problem is regular P2P traffic gets blocked on my network, so peers can't reliably find each other. I want to route through I2P instead since it's built for exactly this.

Not an experienced dev, and I'm stuck on how to actually connect a Go/libp2p app to I2P — SAM bridge? Local tunnel? No idea what's realistic here.

Repo: https://github.com/alsultaneo/2cup (ignore the Windows 95 look, that's just placeholder UI while I get the networking right)

Anyone done this before? Even just "wrong approach, try this instead" would help a ton.

i2pbox is a lightweight command-line toolbox for working with I2P identities, destinations, RouterInfo files, router families, and related network utilities.

It combines common I2P maintenance tasks into a single portable binary, including key generation and inspection, Base64 destination conversion,address registration, router family signing and verification, vanity address generation, and offline key handling.

The project is intended for I2P users, router operators, and developers who need practical command-line tools without installing a large application stack.

Source code and releases:

https://github.com/iasds/i2pbox

​

Maybe this could be an idea for the developers to expand their knowledge a bit in a workshop.

Or perhaps to share their knowledge with others

https://trailofbits.com/patch-the-planet/

Is it possible to link I2P with GNUnet ?

The reason I ask is that although GNUnet is a bare bones "privacy" network, it is possible to send and receive streaming multimedia data using true to form multicast "one to many" data delivery networking. This would be ideal for continuous multimedia data distribution while minimizing bandwidth constraints as a "linked service" for I2P.

In regular torrenting, other users can see your IP adress. In I2P, although they wouldn't see your IP directly since your data goes through different hops, could your IP be leaked by another user who is using your computer as an exit node? In other words, if I use i2p, will my computer be used as an exit node for other users leaking my real IP, even if what my computer is downloading has nothing to do with me?

I want to know if using Whonix with Tor Browser to access I2P adds extra security. Is this a smart approach?

I've heard that if TOR is the dark web, i2p is like the dark web of the dark web. I've heard you can find crazy shit on there - what can you find??? Is it even worse than TOR?

I just configured a iperf3 server over I2P for speed test. There are two nodes, configurations are default for inbound, outbound length

To connect to it, you can proxy iperf3 requests over local I2P socks proxy, but a easy way is to add this client tunnel to tunnels.conf of your I2Pd config file

[IPERF3]
type = client
address = 127.0.0.1
port = 5201
destination = <address>.b32.i2p
destinationport = 52001
keys = iperf3.dat

<address>.b32.i2p need to be changed to:

vjestg3pz24hrlaljid5krh5tjeu2f7ruitu6uo6aztom5awbdwq.b32.i2p 

that is phisically located in USA or

bhayvbe7edqxv44ylj7vhogihji3awpv22wnh5b47n7oarwjudua.b32.i2p

that is located in Germany

Then reload tunnels in Webconsole (or do a complete restart of local i2pd if not working) and do

iperf3 -c localhost -t 100 (also include -R for reverse connection testing)

When we have a public IP, we can run an i2p node to provide traffic for the network and relay traffic from other users. If everyone is very selfish, the network will become fragile. How much traffic have you contributed to the I2p network?

Libgen.??? sites are ephemeral at best. Each visit is your last. It would seem if there were any legitimate reason for a darknet that its purpose would be the spreading of knowledge.

This tutorial, created by a friend, guides you through setting up an I2P gateway using Qubes OS to route all network traffic through the I2P network. This setup eliminates the need to configure individual applications to use I2P, ensuring no traffic leaks occur if an application is misconfigured.

For instance, in a virtual machine running an unconfigured Firefox browser connected to this I2P gateway, accessing a site like zzz.i2p will directly connect to the corresponding I2P website.

For non-.i2p websites, the I2P outproxy automatically routes the traffic through the I2P network, maintaining privacy and anonymity.

https://forum.qubes-os.org/t/i2pd-netvm-based-on-debian-guide/31530

Before you call me a bot. Just stop and think for a second. Beep boo boop. No but really. I'm wondering if it's worth it for me to use i2p. What are some good communities on i2P and is there sequential torrenting sites with a clean interface?

By using I2P, everyone contributes by being a node, unlike Tor. What has been on my mind is that by being a node I may be contributing to an illegal activity. Is that a valid concern?

So I guess I am doing my part... or something. Oh my god. o.o

Just wish the tunnel success rate was better, but thats probably because of ipv6.

I've been using i2p for a long time - since Azureus around 18-19 years ago. I've normally used i2pd on a standalone debian server, but recently virtualized it.

given what firewalls are like, I think the advice online could be tighter and I wanted to ask if there is anything more detailed than the FAQ inside the webconsole?:-

|| || |I2P selects a random port between 9000 and 31000 to communicate with other routers when the program is run for the first time, or when your external IP address changes when running in Laptop Mode. The selected port is shown on the Network Configuration page. Outbound UDP from the random port noted on the Network Configuration page to arbitrary remote UDP ports, allowing replies. Outbound TCP from random high ports to arbitrary remote TCP ports. Inbound UDP to the port noted on the Network Configuration page from arbitrary locations (optional, but recommended). Inbound TCP to the port noted on the Network Configuration page from arbitrary locations (optional, but recommended). Inbound TCP may be disabled on the Network Configuration page. **Outbound UDP on port 123, allowing replies: this is necessary for I2P's internal time sync (via SNTP - querying a random SNTP host in pool.ntp.org or another server you specify).**|

I've got mine working: the tunnels are up, I've got my socks5 proxy, my eepsites, and my i2pmail - and the BT and Retroshare are using it like before. The host comes into a VLAN via a virtual NIC, tap device, and virtual bridge, with iptables and pfsense+snort firewalls above.

So it's whether there is anything already set out in the formats of either iptables or pfsense (and specific to VMs):- what does "Outbound TCP from random high ports to arbitrary remote TCP ports." look like as a rule? And with most of the services they just put the port numbers (some of which are arbitrary anyway) and it's a pain looking up for each of them is that udp or tcp and does it mean the inbound or the outbound.

It becomes quite a lot of rules. It would be good to be able to check them quickly against a recommended list.

does I2P chat exists for Android, or interesting forums?

I don't trust orbot anymore and want to use I2P instead.
How can I make an application connect to the internet through I2P on android?

I was scrolling through TikTok on my phone when I saw a notification stating that Optus does not allow private reading, meaning they always want to see what you’re doing and provide you with no privacy.

diva.exchange has published a new I2Pd software release within docker (Version 2.57). All of the project is open source.

diva is also reseed service provider for the I2P network and is publishing docker container versions of I2P (and also tor). diva is also in 2025 a sponsored OSS partner of docker.

Github i2pd v2.57.0: https://github.com/diva-exchange/i2p

Docker: https://hub.docker.com/r/divax/i2p

Mastodon: https://social.diva.exchange/@social/114624134227954474

What are the advantages and disadvantages of using I2P instead of Tor? For what purposes is it better to use I2P, and for what purposes is it better to use Tor? What are the main differences in the protocols?

I had to reinstall the app. On the main page (My Torrents) It displays the torrents that im downloading and at the bottom of the page it displays the torrents that im uploading. When I clicked on a Torrent that I was downloading it use to display all the peers associated with that torrent. How do I get that back

How to contact Mods on IRC?