Security in p2p networks: survey and research directions
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paper_title: Trusted computing: providing security for peer-to-peer networks

paper_content:

In this paper, we demonstrate the application of trusted computing to securing peer-to-peer (P2P) networks. We identify a central challenge in providing many of the security services within these networks, namely the absence of stable verifiable peer identities. We employ the functionalities provided by trusted computing technology to establish a pseudonymous authentication scheme for peers and extend this scheme to build secure channels between peers for future communications. In support of our work, we illustrate how commands from the trusted computing group (TCG) specifications can be used to implement our approach in P2P networks.
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paper_title: The Sybil Attack

paper_content:

Large-scale peer-to-peer systems face security threats from faulty or hostile remote computing elements. To resist these threats, many such systems employ redundancy. However, if a single faulty entity can present multiple identities, it can control a substantial fraction of the system, thereby undermining this redundancy. One approach to preventing these "Sybil attacks" is to have a trusted agency certify identities. This paper shows that, without a logically centralized authority, Sybil attacks are always possible except under extreme and unrealistic assumptions of resource parity and coordination among entities.
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paper_title: About the Value of Virtual Communities in P2P Networks

paper_content:

The recently introduced peer-to-peer (P2P) systems are currently the most popular Internet applications. This contribution is intended to show that such decentralized architecture could be served as a suitable structure to support virtual communities.
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paper_title: PlanetP: using gossiping to build content addressable peer-to-peer information sharing communities

paper_content:

We introduce PlanetP, content addressable publish/subscribe service for unstructured peer-to-peer (P2P) communities. PlanetP supports content addressing by providing: (1) a gossiping layer used to globally replicate a membership directory and an extremely compact content index; and (2) a completely distributed content search and ranking algorithm that help users find the most relevant information. PlanetP is a simple, yet powerful system for sharing information. PlanetP is simple because each peer must only perform a periodic, randomized, point-to-point message exchange with other peers. PlanetP is powerful because it maintains a globally content-ranked view of the shared data. Using simulation and a prototype implementation, we show that PlanetP achieves ranking accuracy that is comparable to a centralized solution and scales easily to several thousand peers while remaining resilient to rapid membership changes.
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paper_title: Defending against spoofed DDoS attacks with path fingerprint *

paper_content:

In this paper, we propose a new scheme, called ANTID, for detecting and filtering DDoS attacks which use spoofed packets to circumvent the conventional intrusion detection schemes. The proposed anti-DDoS scheme intends to complement, rather than replace conventional schemes. By embedding in each IP packet a unique path fingerprint that represents the route an IP packet has traversed, ANTID is able to distinguish IP packets that traverse different Internet paths. In ANTID, a server maintains for each of its communicating clients the mapping from the client's IP address to the corresponding path fingerprint. The construction and renewal of these mappings is performed in an on-demand fashion that helps to reduce the cost of maintenance. With presence of the mapping table, the onset of a spoofed DDoS attack can be detected by observing a surge of spoofed packets. Consequently, spoofed attack packets are filtered so as to sustain the quality of protected Internet services. ANTID is lightweight, robust, and incrementally deployable. Our experiment results showed that the proposed scheme can detect 99.95% spoofed IP packets and can discard them with little collateral damage to legitimate clients. It also showed that the higher the aggregated attack rate is, the sooner the attack can be detected.
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paper_title: Byzantine Fault Tolerant Public Key Authentication in Peer-to-Peer Systems

paper_content:

We describe Byzantine fault tolerant authentication, a mechanism for public key authentication in peer-to-peer systems. Authentication is done without trusted third parties, tolerates Byzantine faults and is eventually correct if more than a threshold of the peers are honest. This paper addresses the design, correctness, and fault tolerance of authentication over insecure asynchronous networks. An anti-entropy version of the protocol is developed to provide lazy authentication with logarithmic messaging cost. The cost implications of the authentication mechanism are studied by simulation.
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paper_title: Overcoming free-riding behavior in peer-to-peer systems

paper_content:

While the fundamental premise of peer-to-peer (P2P) systems is that of voluntary resource sharing among individual peers, there is an inherent tension between individual rationality and collective welfare that threatens the viability of these systems. This paper surveys recent research at the intersection of economics and computer science that targets the design of distributed systems consisting of rational participants with diverse and selfish interests. In particular, we discuss major findings and open questions related to free-riding in P2P systems: factors affecting the degree of free-riding, incentive mechanisms to encourage user cooperation, and challenges in the design of incentive mechanisms for P2P systems.
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paper_title: Tarzan: a peer-to-peer anonymizing network layer

paper_content:

Tarzan is a peer-to-peer anonymous IP network overlay. Because it provides IP service, Tarzan is general-purpose and transparent to applications. Organized as a decentralized peer-to-peer overlay, Tarzan is fault-tolerant, highly scalable, and easy to manage.Tarzan achieves its anonymity with layered encryption and multi-hop routing, much like a Chaumian mix. A message initiator chooses a path of peers pseudo-randomly through a restricted topology in a way that adversaries cannot easily influence. Cover traffic prevents a global observer from using traffic analysis to identify an initiator. Protocols toward unbiased peer-selection offer new directions for distributing trust among untrusted entities.Tarzan provides anonymity to either clients or servers, without requiring that both participate. In both cases, Tarzan uses a network address translator (NAT) to bridge between Tarzan hosts and oblivious Internet hosts.Measurements show that Tarzan imposes minimal overhead over a corresponding non-anonymous overlay route.
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paper_title: Crowds: Anonymity for Web Transactions

paper_content:

In this paper we introduce a system called Crowds for protecting users' anonymity on the world-wide-web. Crowds, named for the notion of “blending into a crowd,” operates by grouping users into a large and geographically diverse group (crowd) that collectively issues requests on behalf of its members. Web servers are unable to learn the true source of a request because it is equally likely to have originated from any member of the crowd, and even collaborating crowd members cannot distinguish the originator of a request from a member who is merely forwarding the request on behalf of another. We describe the design, implementation, security, performance, and scalability of our system. Our security analysis introduces degrees of anonymity as an important tool for describing and proving anonymity properties.
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paper_title: Pricing via processing or combatting junk mail

paper_content:

We present a computational technique for combatting junk mail in particular and controlling access to a shared resource in general. The main idea is to require a user to compute a moderately hard, but not intractable, function in order to gain access to the resource, thus preventing frivolous use. To this end we suggest several pricing Junctions, based on, respectively, extracting square roots modulo a prime, the Fiat-Shamir signature scheme, and the Ong-Schnorr-Shamir (cracked) signature scheme.
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paper_title: Using speakeasy for ad hoc peer-to-peer collaboration

paper_content:

Peer-to-peer systems appear promising in terms of their ability to support ad hoc, spontaneous collaboration. However, current peer-to-peer systems suffer from several deficiencies that diminish their ability to support this domain, such as inflexibility in terms of discovery protocols, network usage, and data transports. We have developed the Speakeasy framework, which addresses these issues, and supports these types of applications. We show how Speakeasy addresses the shortcomings of current peer-to-peer systems, and describe a demonstration application, called Casca, that supports ad hoc peer-to-peer collaboration by taking advantages of the mechanisms provided by Speakeasy.
---
paper_title: Byzantine Fault Tolerant Public Key Authentication in Peer-to-Peer Systems

paper_content:

We describe Byzantine fault tolerant authentication, a mechanism for public key authentication in peer-to-peer systems. Authentication is done without trusted third parties, tolerates Byzantine faults and is eventually correct if more than a threshold of the peers are honest. This paper addresses the design, correctness, and fault tolerance of authentication over insecure asynchronous networks. An anti-entropy version of the protocol is developed to provide lazy authentication with logarithmic messaging cost. The cost implications of the authentication mechanism are studied by simulation.
---
paper_title: Impeding attrition attacks in P2P systems

paper_content:

P2P systems are exposed to an unusually broad range of attacks. These include a spectrum of denial-of-service, or attrition, attacks from low-level packet flooding to high-level abuse of the peer communication protocol. We identify a set of defenses that systems can deploy against such attacks and potential synergies among them. We illustrate the application of these defenses in the context of the LOCKSS digital preservation system.
---
paper_title: Pricing via processing or combatting junk mail

paper_content:

We present a computational technique for combatting junk mail in particular and controlling access to a shared resource in general. The main idea is to require a user to compute a moderately hard, but not intractable, function in order to gain access to the resource, thus preventing frivolous use. To this end we suggest several pricing Junctions, based on, respectively, extracting square roots modulo a prime, the Fiat-Shamir signature scheme, and the Ong-Schnorr-Shamir (cracked) signature scheme.
---
paper_title: Using speakeasy for ad hoc peer-to-peer collaboration

paper_content:

Peer-to-peer systems appear promising in terms of their ability to support ad hoc, spontaneous collaboration. However, current peer-to-peer systems suffer from several deficiencies that diminish their ability to support this domain, such as inflexibility in terms of discovery protocols, network usage, and data transports. We have developed the Speakeasy framework, which addresses these issues, and supports these types of applications. We show how Speakeasy addresses the shortcomings of current peer-to-peer systems, and describe a demonstration application, called Casca, that supports ad hoc peer-to-peer collaboration by taking advantages of the mechanisms provided by Speakeasy.
---
paper_title: Byzantine Fault Tolerant Public Key Authentication in Peer-to-Peer Systems

paper_content:

We describe Byzantine fault tolerant authentication, a mechanism for public key authentication in peer-to-peer systems. Authentication is done without trusted third parties, tolerates Byzantine faults and is eventually correct if more than a threshold of the peers are honest. This paper addresses the design, correctness, and fault tolerance of authentication over insecure asynchronous networks. An anti-entropy version of the protocol is developed to provide lazy authentication with logarithmic messaging cost. The cost implications of the authentication mechanism are studied by simulation.
---
paper_title: Crowds: Anonymity for Web Transactions

paper_content:

In this paper we introduce a system called Crowds for protecting users' anonymity on the world-wide-web. Crowds, named for the notion of “blending into a crowd,” operates by grouping users into a large and geographically diverse group (crowd) that collectively issues requests on behalf of its members. Web servers are unable to learn the true source of a request because it is equally likely to have originated from any member of the crowd, and even collaborating crowd members cannot distinguish the originator of a request from a member who is merely forwarding the request on behalf of another. We describe the design, implementation, security, performance, and scalability of our system. Our security analysis introduces degrees of anonymity as an important tool for describing and proving anonymity properties.
---
paper_title: Chord: A scalable peer-to-peer lookup service for internet applications

paper_content:

A fundamental problem that confronts peer-to-peer applications is to efficiently locate the node that stores a particular data item. This paper presents Chord, a distributed lookup protocol that addresses this problem. Chord provides support for just one operation: given a key, it maps the key onto a node. Data location can be easily implemented on top of Chord by associating a key with each data item, and storing the key/data item pair at the node to which the key maps. Chord adapts efficiently as nodes join and leave the system, and can answer queries even if the system is continuously changing. Results from theoretical analysis, simulations, and experiments show that Chord is scalable, with communication cost and the state maintained by each node scaling logarithmically with the number of Chord nodes.
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paper_title: A scalable content-addressable network

paper_content:

Hash tables - which map "keys" onto "values" - are an essential building block in modern software systems. We believe a similar functionality would be equally valuable to large distributed systems. In this paper, we introduce the concept of a Content-Addressable Network (CAN) as a distributed infrastructure that provides hash table-like functionality on Internet-like scales. The CAN is scalable, fault-tolerant and completely self-organizing, and we demonstrate its scalability, robustness and low-latency properties through simulation.
---
paper_title: Impeding attrition attacks in P2P systems

paper_content:

P2P systems are exposed to an unusually broad range of attacks. These include a spectrum of denial-of-service, or attrition, attacks from low-level packet flooding to high-level abuse of the peer communication protocol. We identify a set of defenses that systems can deploy against such attacks and potential synergies among them. We illustrate the application of these defenses in the context of the LOCKSS digital preservation system.
---
paper_title: PlanetP: using gossiping to build content addressable peer-to-peer information sharing communities

paper_content:

We introduce PlanetP, content addressable publish/subscribe service for unstructured peer-to-peer (P2P) communities. PlanetP supports content addressing by providing: (1) a gossiping layer used to globally replicate a membership directory and an extremely compact content index; and (2) a completely distributed content search and ranking algorithm that help users find the most relevant information. PlanetP is a simple, yet powerful system for sharing information. PlanetP is simple because each peer must only perform a periodic, randomized, point-to-point message exchange with other peers. PlanetP is powerful because it maintains a globally content-ranked view of the shared data. Using simulation and a prototype implementation, we show that PlanetP achieves ranking accuracy that is comparable to a centralized solution and scales easily to several thousand peers while remaining resilient to rapid membership changes.
---

Title: Security in P2p Networks: Survey and Research Directions
Section 1: Introduction
Description 1: Provide an overview of P2P networks and introduce the various security issues.

Section 2: Overlay Networks
Description 2: Discuss the classification of overlay networks, their structures, and relevant security concerns.

Section 3: User Community
Description 3: Explore the challenges related to the user community in P2P networks, particularly high node transience and lack of centralized authority.

Section 4: Trust and Social Profiles
Description 4: Explain the importance of cooperation in P2P networks and the use of reputation schemes to build trust and incentivize good behavior.

Section 5: Identification vs. Anonymity
Description 5: Analyze the balance between node identification and anonymity, along with related security risks and existing solutions.

Section 6: Node Authentication and Access Control
Description 6: Review methods of node authentication and access control, including digital signatures and ACLs.

Section 7: Content
Description 7: Address issues related to content availability, integrity, and authentication, and discuss strategies for replication and protection.

Section 8: Analysis
Description 8: Present a comparative analysis of security issues in different P2P architectures using detailed tables summarizing the protection mechanisms against various attacks.

Section 9: Conclusions and Research Directions
Description 9: Summarize the state of security in P2P networks and outline potential future research directions in areas such as node cooperation and P2P systems for mobile networks.