What Is I2P Used for and Is It Secure?

June 12, 2025 By Janne Smith No Comments 5 minutes

Invisible Internet Project (I2P) is a P2P anonymous network layer that conceals your browsing activities and protects you from censorship. It enables secure and pseudonymous communication over the internet. I2P routes the internet traffic through a decentralized and encrypted network.

I2P encrypts your data multiple times and routes it through volunteer-operated nodes similar to TOR. But, are they similar? This guide briefly walks you through what is I2P, its pros and cons, and I2P vs TOR.

Note: Connecting to a VPN before enabling I2P improves online security. Your ISP will then only see encrypted VPN traffic. It offers extra privacy even before the traffic enters the I2P network.

What Is I2P?

I2P is an anonymous overlay network that protects user privacy and resists censorship. It enables you to securely communicate over the internet by routing your internet traffic via a decentralized and encrypted network. Its use cases include:

• Anonymous browsing
• Hosting hidden services (blogs, forums and marketplaces)
• Secure peer-to-peer communication
• File sharing

Features of I2P

I2P is a highly secure network, and here are the features that make it recommended for resisting censorship and surveillance:

• Anonymity: It conceals the IP addresses of the sender and receiver.
• Decentralized Network: There’s no central authority, which avoids shutdowns.
• End-to-End Encryption: Data is encrypted multiple times and routed via volunteer-operated nodes.
• Internal Sites: Websites hosted with I2P are only accessible from within the network.
• Garlic Routing: This is an enhanced version of onion routing where multiple messages are bundled to obscure traffic analysis.

How Does l2P Work?

How does this secure network really work? To make it simpler, here’s a brief breakdown of I2P’s working.

The first step is joining the network. When you start the I2P software, it connects to the floodfill of routers, which is similar to TOR’s directory servers. Later, the router builds its profile of the network by exchanging data with other peers.

Following this, it uses unidirectional tunnels, i.e., inbound and outbound. Each tunnel consists of multiple hops (2-4 routers). Every hop knows its immediate predecessor and successor.

Instead of sending single-layer encrypted messages, I2P bundles multiple messages together as cloves of garlic with additional encryption. This makes traffic analysis harder. Meanwhile, when you want to send a message, your outbound tunnel forwards it through several hops. Once the message reaches the inbound tunnel, it is decrypted layer by layer.

All websites and services inside I2P use the .i2p addresses. Instead of revealing an IP, the service is only accessed through its public key, hashed into an address. Following that, all requests are routed through tunnels, which hide the host and the visitor.

What Are the Pros and Cons of I2P

As secure as I2P is, the cons still exist. Here’s a list of the pros and cons of I2P:

Pros of the I2P Network

• Strong Anonymity: The network hides the sender’s and the receiver’s IP addresses by layered encryption and routing.
• End-to-End Encryption: All internet traffic is routed multiple times and sent through different nodes for enhanced privacy.
• Garlic Routing: The network bundles multiple messages together. This helps defend against traffic analysis to improve security.
• Decentralized Network: There are no central servers or control points, which prevents censorship and shutdowns.
• Internal Services: It supports anonymous websites and services that exist within the network.

Cons of the I2P Network

• Steep Learning Curve: The setup can be complex for non-technical users.
• Limited Access to Clearnet: It is designed for communication within the network. This doesn’t provide native access to regular websites like Tor.
• Small User Base: It has a smaller user base. This can limit content and service diversity.
• Slow Speeds: Due to heavy encryption, connection speeds can be significantly slower than TOR or the standard internet.
• Smaller Community: There’s less documentation, tutorials, and third-party tools.
• Not Suitable for Real-Time Services: Expect speed limitations due to speed limitations. Voice or video calls might perform poorly on I2P.

What Is the Difference Between TOR and I2P?

TOR and I2P seem similar, but they work quite differently:

Final Note

This network offers advanced online anonymity and resists censorship. Its decentralized, encrypted network masks the network traffic between the sender and the receiver through advanced garlic routing. However, it offers slower speeds. But, it’s privacy-focused architecture makes it ideal for hosting hidden services, anonymous browsing and secure messaging.