H-P2PSIP: Interconnection of P2PSIP domains for Global Multimedia Services based on a Hierarchical DHT Overlay Network

The IETF P2PSIP WG is currently standardising a protocol for distributed mul- timedia services combining the media session functionality of SIP and the decentralised distribution and localisation of resources in peer-to-peer networks. The current P2PSIP scenarios only consider the infrastructure for the connectivity inside a single domain. This paper proposes an extension of the current work to a hierarchical multi-domain scenario: a two level hierarchical peer-to-peer overlay architecture for the interconnection of different P2PSIP domains. The purpose is the creation of a global decentralised multimedia services in enterprises, ISPs or community networks. We present a study of the Routing Performance and Routing State in the particular case of a two-level Distributed Hash Table Hierarchy that uses Kademlia. The study is supported by an analytical model and its validation by a peer-to-peer simulator.En prens

Taxonomy of P2P Applications

Peer-to-peer (p2p) networks have gained immense popularity in recent years and the number of services they provide continuously rises. Where p2p-networks were formerly known as file-sharing networks, p2p is now also used for services like VoIP and IPTV. With so many different p2p applications and services the need for a taxonomy framework rises. This paper describes the available p2p applications grouped by the services they provide. A taxonomy framework is proposed to classify old and recent p2p applications based on their characteristics

Routing Performance in Hierarchical DHT-based Overlay Networks

The scalability properties of DHT based overlay networks is considered satisfactory. However, in large scale systems this might still cause a problem since they have a logarithmic complexity depending. Further, they only provide a one dimensional structure and do not make use on inherent clustering properties of some applications (e.g. P2PVoIP or locality aware overlays). Thus, structures based on a hierarchical approach can have performance as well as structural advantages. In this paper, a generic hierarchical architecture based on super-peers is presented where a peer ID is composed by a Prefix ID and a Suffix ID. Prefix ID is only routed at the super-peer level and the Suffix ID at the peer level. We specifically analyse the Routing Performance of this approach within the context of two specific overlays, viz. CAN and Kademlia.This work has been partially supported by the European Union under the IST Content NoE (FP6-2006-IST-038423) and by the BioGridNet project (CAM, S-0505/TIC-0101).Publicad

Redes overlay peer-to-peer baseadas em SIP

As redes Peer-to-peer (P2P) tem vindo a ganhar popularidade na internet, devido ao aumento do número de utilizadores e de serviços de natureza distribuída, como a partilha de ficheiros, e as chamadas de voz sobre IP (VoIP). A criação deste tipo de redes, baseando-se em soluções abertas como o SIP, pode facilitar a criação de novos tipos de serviços, assim como permitir uma mais fácil integração de diferentes serviços. Neste trabalho foi desenvolvida uma implementação JAVA, capaz de criar redes P2PSIP com um ou dois níveis hierárquicos. A comunicação entre os nós da rede P2P, ´é feita através de um protocolo totalmente baseado em SIP. Como algoritmos a utilizar pelo overlay P2P, foram implementados o algoritmo Chord e EpiChord. Para comprovar o funcionamento da implementação JAVA, foram efectuados testes num ambiente real, recorrendo a uma topologia de rede emulada com o CORE

Benefits of an Implementation of H-P2PSIP

[Paper presented at:] Second International Conference on Advances in P2P Systems. AP2PS 2010. October 25-30, Florence (Italy)In this paper, we report on the results of experiments with an implementation of H-P2PSIP, which allows the exchange of information among different DHTs (Distributed Hash Tables) making use of a hierarchical architecture. This paper validates our previous H-P2PSIP proposal in an environment with a real TCP/IP stack close to a real scenario. The results show how the benefits of this real H-P2PSIP implementation in terms of routing performance (number of hops), delay and routing state (number of routing entries) are better than a flat DHT overlay network and how the exchange of information among different DHT overlay networks is feasible.This work has been supported by the FP7 TREND Grant (agreement No. 257740) and by the Regional Government of Madrid under the MEDIANET project (CAM, S2009/TIC-1468).European Community's Seventh Framework ProgramPublicad

Design and implementation of a hierarchical SIP-based peer-to-peer network

Peer-to-peer (P2P) has gained popularity in Internet due to the increased number of users and distributed services such as file sharing and voice calls over IP (VoIP). Currently, the most popular P2P networks store information pertaining to its resources in a distributed manner using Distributed Hash Tables (DHT). In this type of networks, the peers are deterministically positioned and resources are also allocated to each peer for indexing in a deterministic manner. This paper presents a new hierarchical SIP based P2P network. A pure SIP solution was used because we believe that an open solution such as SIP can facilitate the creation of new types of services and permit the facilitated integration of different services. A two level hierarchy is used and is aimed towards the improvement of network efficiency where peers can move dynamically from one layer to another according to its available resources. In addition to this, the proposed implementation architecture allows the independence of the underlying DHT algorithms. The proposed architecture was implemented and tested in a realistic scenario which was created inside a Linux cluster. The DHT algorithms, Chord and EpiChord, were also implemented and used to index resources in either flat or hierarchical networks. Results indicate that the proposed two-layer hierarchy significantly improves the P2P overlay performance while in the presence of peers with limitations.(undefined

Analysis of relod.net, a basic implementation of the RELOAD protocol for peer-to-peer networks

Actas de: XI Jornadas de Ingeniería Telemática (JITEL 2013) celebradas en Granada, 28-30 Octubre 2013. La web del evento es: http://dtstc.ugr.es/jitel2013/#The P2PSIP Working Group is chartered to develop protocols and mechanisms for the use of SIP in distributed environments, thus minimizing the need for centralized servers. Under this premise, the RELOAD protocol was created, whose design was generalized to accept other applications with similar requirements, and which is currently in process of standardization by the IETF. In this paper, we present a basic implementation and an analysis of this protocol proposed standard, given the great interest displayed in recent years by the scientific and business community in issues related to peerto- peer networks. Later, we conduct several experiments in order to validate its correct operation in real scenarios and provide feedback in relation with the current specificationThis research was supported in part by the Comunidad de Madrid grant S-2009/TIC-1468 (MEDIANET project).Publicad

Validation of H-P2PSIP, a scalable solution for interoperability among different overlay networks

This paper reports the results of experiments from an implementation of H-P2PSIP, a hierarchical overlay architecture based on the ongoing work in the IETF P2PSIP Working Group. This architecture allows the exchange of information among different independent overlay networks through the use of a two-layer architecture based on super-peers and hierarchical identifiers. The validation of this proposal is based on a Linux based real implementation where we have used four different scenarios with 1,000 peers in order to perform different experiments. We have obtained results for different parameters such as routing performance (number of hops), delay, routing state (number of overlay routing entries) and bandwidth consumption.This research was supported in part by the European Commission Seventh Framework Programme under grant agreement n 25774 (TREND Network of Excellence), Comunidad de Madrid grant S-2009/TIC-1468 (MEDIANET project) and Spanish MICINN grant TEC2011-29688-C02-02 (eeCONTENT project).Publicad

Applying low discrepancy sequences for node-ID assignment in P2PSIP

The IETF P2PSIP Working Group is currently designing a standard overlay protocol, named RELOAD, that employs a centralized node identifier (node-id) assignment for security reasons. Given this scenario, we propose the utilization of a Low Discrepancy Sequence (LDS) for the assignment of node-ids in the P2PSIP architecture. We perform an analytical and simulation study considering a Chord DHT that demonstrates that using a LDS-based node-id assignment guarantees a fair distribution of the node's zone of responsibility, even in high churn scenarios. Previous studies have shown that a fairer distribution of the zones of responsibility sizes leads to a fairer distribution of the storage and routing load. Therefore we conclude that the proposed LDS node-id assignment provides these features without adding any extra overhead.This work has been partially supported by the EU through the FP7 TREND Project (257740), the Spanish Government through the T2C2 project (TIN2008-06739-C04-01), and the Regional Government of Madrid through the MEDIANET project (S-2009/TIC- 1468).Publicad