I2P is an attempt to bring a decentralized anonymizing network on top of internet. In this network you are able to make use of the I2P-related applications which currently consists of many regular internet applications with IM, chat, forums and p2p. The reason it is on the RBOSE wiki is because it is an open source design for creating secure networks.
How is I2P licensed? Since the I2P project makes use of several libraries (all of them open to some degree) it is a bit more complex then bound to a single license form.
A full list of licenses for the different part of the project can be found at http://www.i2p2.i2p.to/licenses.html .
I2P works in a very decentralized fashion. Your computer will create a plan (tunnel) for which nodes the communication will go through. This tunnel will be created using an algorithm that involves using random known peer. Tunnel is also rebuilt during use of I2P.
However, I2P is not a darknet by default, but if you read the documentation it is not hard to understand what to do in order to make it one.
Quoting from the documentation regarding bootstrapping (a.k.a. the absolutely first thing the software does, in order to join the network):
- The netDb is decentralized, however you do need at least one reference to a peer so that the integration process ties you in. This is accomplished by "reseeding" your router with the RouterInfo of an active peer - specifically, by retrieving their routerInfo-$hash.dat file and storing it in your netDb/ directory. Anyone can provide you with those files - you can even provide them to others by exposing your own netDb directory.
- http://www.i2p2.de/ - Official project website
- a.study.in.decentralized.anonymous.and.secure.networks - a study on several solutions, I2P included