Security has become a primary concern in order to provide protected communication between mobile nodes in a hostile environment. Unlike the wire line networks, the unique characteristics of mobile ad hoc networks pose a number of nontrivial challenges to security design, such as open peer-to-peer network architecture, shared wireless medium, stringent resource constraints, and highly dynamic ne...

This paper presents the design, implementation, and evaluation of the replication framework of Deno, a decentralized, peer-to-peer object-replication system targeted for weakly connected environments. Deno uses weighted voting for availability and pair-wise, epidemic information flow for flexibility. This combination allows the protocols to operate with less than full connectivity, to easily ad...

Software-Defined Networks’ technologies introduce programmatic ways to reorganize the network logical topology. To achieve this, the switches in the network interact with a set of controllers, these controllers can dynamically update the switches configuration based in received events. A possible practical field of use of Software-Defined Networks’ is the one called Reactive Routing. On Reactiv...

Studies on the large scale peer-to-peer (P2P) network like Gnutella have shown the presence of large number of free riders. Moreover, the open and decentralized nature of P2P network is exploited by malicious users who distribute unauthentic or harmful contents. Despite the existence of a number of trust management schemes in the literature for combating against free riding and distribution of ...

The main focus of recent time synchronization research is developing power-efficient synchronization methods that meet pre-defined accuracy requirements. However, an aspect that has been often overlooked is the high dynamics of the network topology due to the mobility of the nodes. Employing existing flooding-based and peer-to-peer synchronization methods, are networked robots still be able to ...

P2P systems are characterised by large-scale distribution and high degree of architectural dynamics caused by their lack of central coordination. In such an environment, it is notoriously hard to guarantee a good quality of service. Simulation can help to validate network designs and protocols, but most existing simulation approaches cannot cope with unbounded dynamic change of network topology...

This paper studies local-control strategies to estimate the size of a certain event affecting an arbitrary connected subset of nodes in a network. For example, our algorithms allow nodes in a peer-to-peer system to explore the remaining connected components after a Denial-ofService attack, or nodes in a sensor network to assess the magnitude of a certain environmental event. In our model, each ...

The Internet is a cooperative and decentralized network built out of millions of participants that share large amounts of information. Peer-to-peer (P2P) systems go hand-in-hand with this huge decentralized network, where each individual node can serve content as well as request it. In this scenario, thematic search algorithms should lead to and benefit from the emergence of semantic communitie...

A network attack is a set of network elements that are disabled by an adversary. The goal for the attack is to produce the most possible damage to the network in terms of network connectivity by disabling the least possible number of network elements. We show that the problem of finding the optimal attack in a serverless network is NP-Complete even when only edges or nodes are considered for di...

This paper provides a quantative comparison of the efficiency of the self-organized construction processes of the P-Grid and FreeNet peer-to-peer systems. Starting from a defined, realistic network topology we simulate the construction of their access structures and measure the incurred message load and memory usage for routing tables. Besides these results our experimental setup may also be us...