Benefits on using H-P2PSIP in mobile environments

Proceeding of: VIII Jornadas de Ingeniería Telemática (JITEL '09), Universidad Politécnica de Cartagena, Cartagena, Murcia, 15-17 de septiembre de 2009The use of peer-to-peer technologies is increasing everyday and the improvement of mobility technologies is a reality. Now, it is expected that peer-to-peer applications run on mobile devices, but the conjunction of these two technologies is an open research issue. The user mobility impacts on the churn suffered by peer-to-peer networks and consequently it impacts on their performance. Therefore, some mechanisms are necessary to minimize this undesirable effect. Our proposal tries to solve this problem by using a Hierarchical P2PSIP architecture where different overlays are used for different peer mobility behaviours and they are interconnected between them through an interconnection overlay. In this way it is possible for peers that share the same behaviour to choose a certain protocol or to optimize some functionality that suits best with their mobility situation, while maintaining connectivity with all peers.This research work is being supported by the European Commission under the IST Content Network of Excellence3 (FP6-2006-IST-038423), by the Regional Government of Madrid under the BioGridNet4 project (CAM, S-0505/TIC- 0101) and by the Ministry of Science and Innovation under the CONPARTE project (MEC, TEC2007-67966-C03-03/TCM).No publicad

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

Enabling Layered Video Coding for IMS-Based IPTV Home Services

Nowadays IPTV services are gaining attention from both providers and end users. There is a large effort toward the integration of these services into emerging next-generation network architectures. In particular, one of the most relevant solutions is being proposed by ETSI-TISPAN and is based on the IP multimedia subsystem. This article focuses on introducing layered video coding into TISPAN IMS-based IPTV architecture, allowing cost-effective efficient solutions both for residential users and providers (e.g., flexible support of heterogeneous devices, live mosaics, adaptive video quality based on device and/or network capabilities). The advantages of using layered video coding in the TISPAN IPTV solution are analyzed and illustrated with a set of use cases. Furthermore, this solution has been integrated into a multimedia testbed in order to validate the presented proposal

Distributed Management of Application Layer Multicast Trees for IPTV Services

Este trabajo es una ponencia recogida en el IX Jornadas de Ingeniería Telemática (JITEL 2010), celebradas en la Universidad de Valladolid, los días 29 de septiembre y 1 de octubre de 2010 en Valladolid (España). La web del evento es http://jitel2010.tel.uva.es/IP multicast is an eff cient mechanism to distribute IPTV content towards multiple users, but nowadays Internet Providers f lter out this kind of traff c, mainly due to security and accounting issues. In order to overcome this f ltering, the same idea of IP multicast can be implemented at the end user terminals, but implementing multicast trees at the application layer, also known as Application Layer Multicast (ALM). ALM has some drawbacks, mainly due to dynamic behavior of users, joining and leaving the trees. In order to minimize the impact of this behavior, this paper proposes a distributed management for ALM in IPTV, instead of a centralized one, where some nodes connected to a tree will be on charge of the management of that tree. Furthermore, all nodes are dynamically conf gured with the substitute of its parent node in order to accelerate the reconnection process. Results presented in this article show that this proposal provides fast reconstructions and low management load per node, while keeping a balanced tree topology.Este artículo está financiado parcialmente por el proyecto MEDIANET (S-2009/TIC-1468) de la Comunidad de Madrid y por la Cátedra Telefónica en Internet del Futuro para la Productividad de la Universidad Carlos III de Madrid.Publicad

P2P vs. IP multicast: comparing approaches to IPTV streaming based on TV channel popularity

Already a popular application in the Internet, IPTV is becoming, among the service providers, a preferred alternative to conventional broadcasting technologies. Since many of the existing deployments have been done within the safe harbor of telco-owned networks, IP multicast has been the desired streaming solution. However, previous studies showed that the popularity of the TV channels follows the Pareto principle, with the bulk of TV channels being watched only by a small fraction of viewers. Recognizing the potential scalability issues, we believe that multicast streaming approach may not be desirable for unpopular TV channels, especially when there are many such channels in the provider's service package. For this reason, the peer-to-peer content distribution paradigm is seen as an alternative, in particular for non-popular content. In order to analyse its viability, in this paper we perform a comparative analysis between IP multicast and a peer-to-peer overlay using unicast connections as streaming approaches, in the context of channels with different degrees of popularity. The analysis targets the bandwidth utilization, video quality and scalability issues, and our findings show that while multicast is always more efficient, peer-to-peer has a comparable performance for unpopular channels with a low number of viewers.This article has been partially supported by the Spanish Ministry of Science and Innovation through the CONPARTE project (TEC2007-67966-C03-03/TCM), and by the Madrid Community through the MEDIANET project (S2009- TIC1468)Publicad

Supporting mobility in an IMS-based P2P IPTV service: A proactive context transfer mechanism

In recent years, IPTV has received an increasing amount of interest from the industry, commercial providers and the research community, alike. In this context, standardization bodies, such as ETSI and ITU-T, are specifying the architecture of IPTV systems based on IP multicast. An interesting alternative to support the IPTV service delivery relies on the Peer-to-Peer (P2P) paradigm to distribute and push the streaming effort towards the network edge. However, while P2P IPTV was studied in fixed access technologies, there has been little attention paid to the implications arising in mobile environments. One of these involves the service handover when the user moves to a different network. By analyzing previous work from the perspective of an IPTV service, we concluded that a proactive approach is necessary for the handling of inter-network handovers. In this paper, we propose a new general handover mechanism for the IP Multimedia Subsystem (IMS), while studying its applicability to a P2P IPTV service. Our solution, called proactive context transfer service, incorporates the existing IEEE 802.21 technology in order to minimize the handover delay. The proposal is validated by comparing it against solutions derived from previous work.This article has been partially granted by the Spanish MEC through the CONPARTE project (TEC2007–67966-C03–03/TCM) and by the Madrid Community through the MEDIANET project (S-2009/TIC-1468).Publicad

Enabling global multimedia distributed services based on hierarchical DHT overlay networks

Providing innovating multimedia services is a high priority for service providers. Due to the high traffic volume created by multimedia content, the use of decentralised services can lead to better solutions. Starting from the ongoing work of P2PSIP, we define a simple way to interconnect different domains using peer-to-peer networks. We define the needed signalling to provide connectivity between different domains based on P2PSIP. This fact allows an easier deployment of global decentralised multimedia services. We validate the proposed solution through an analytical and experimental study of the routing performance and routing state for two possible scenarios

Supporting mobility in an IMS-based P2P IPTV service: A proactive context transfer mechanism

Abstract In recent years, IPTV has received an increasing amount of interest from the industry, commercial providers and the research community, alike. In this context, standardization bodies, such as ETSI and ITU-T, are specifying the architecture of IPTV systems based on IP multicast. An interesting alternative to support the IPTV service delivery relies on the peer-to-peer (P2P) paradigm to distribute and push the streaming effort towards the network edge. However, while P2P IPTV was studied in fixed access technologies, there has been little attention paid to the implications arising in mobile environments. One of these involves the service handover when the user moves to a different network. By analyzing previous work from the perspective of an IPTV service, we concluded that a proactive approach is necessary for the handling of inter-network handovers. In this paper, we propose a new general handover mechanism for the IP Multimedia Subsystem (IMS), while studying its applicability to a P2P IPTV service. Our solution, called Proactive Context Transfer Service, incorporates the existing IEEE 802.21 technology in order to minimize the handover delay. The proposal is validated by comparing it against solutions derived from previous work