Abstract:
In the last twenty years P2P technology has begun to spread, mainly because of the increasing need of sharing a large quantity of files. Critical operations such as the exchanging of messages or the search of a file are governed by specific routing mechanisms, that depend on the different P2P structures which are involved.
In this thesis we will first present different types of routing protocols, and we will highlight the structure and the mechanisms by which they carry out the update of the contacts and the transfer of files over a network. We will then present some of the weaknesses of which these protocols are suffering, showing how their routing mechanisms can be used in a wrong way to produce unexpected behaviors by the hosts. We will then show some of the countermeasures adopted in order to mitigate the effects of these attacks. In the last part of the thesis we will first use the Peersim simulator to simulate some of the known routing attacks to the Pastry protocol, we will then simulate some new attacks, and we will finally discuss some possible countermeasures.
