Obtaining user feedback (using votes) is essential in ranking user-generated online content. However, any online voting system is susceptible to the Sybil attack where adversaries can out-vote real users by creating several Sybil identities. In this paper, we present SumUp, a Sybilresilient online content rating system that leverages trust networks among users to defend against Sybil attacks wi...

Online content sharing services allow users to find and share content ranging from news articles (Digg) to videos (YouTube) to URLs (StumbleUpon). Generally, such social content sites allow users to create accounts, declare friendships, upload and rate content, and locate new content by leveraging the aggregated ratings of others. For example, most highly rated content typically appears on the ...

Mobile ad-hoc networks (MANETs) are well known to be susceptible to various attacks, due to features such as lack of centralized control, dynamic topology, limited physical security and energy constrained operations. In this paper, we focus on preventing Sybil attack and Intruder nodes (malicious node). We are presenting a novel and secure authentication of nodes as soon as they comes in to the...

Multi-robot networks use wireless communication to provide wide-ranging services such as aerial surveillance and unmanned delivery. However, effective coordination between multiple robots requires trust, making them particularly vulnerable to cyber-attacks. Specifically, such networks can be gravely disrupted by the Sybil attack, where even a single malicious robot can spoof a large number of f...

In this paper, we assess the protection mechanisms entered into recent clients to fight against the Sybil attack in KAD, a widely deployed Distributed Hash Table. We study three main mechanisms: a protection against flooding through packet tracking, an IP address limitation and a verification of identities. We evaluate their efficiency by designing and adapting an attack for several KAD clients...

The infrastructure of a Mobile Adhoc Network (MANET) has no routers for routing and all nodes must share the same routing protocol to assist each other while transmitting messages. Almost all common routing protocols at present consider performance as first priority and have little defense capability against the malicious nodes. Many researchers have proposed protocols of higher safety to defen...

Neighbor discovery is an important part of many protocols for wireless adhoc networks, including localization and routing. When neighbor discovery fails, communications and protocols performance deteriorate. In networks affected by relay attacks, also known as wormholes, the failure may be more subtle. The wormhole may selectively deny or degrade communications. In this article we present Mobil...

Ad hoc networks are made of a group of portable terminals with wireless transmitter as multi-hops provisional autonomy system. Ad hoc networks are very easy to be attacked by various kinds of network attacks, as the limited resources, dynamic topology and open communication channel and so on. Wormhole attack is an internal attack means against routing protocols in the Ad hoc networks,The resear...