75 research outputs found
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
Reducing query overhead through route learning in unstructured peer-to-peer network
Cataloged from PDF version of article.In unstructured peer-to-peer networks, such as Gnutella, peers propagate query messages towards the resource holders by flooding them through the network. This is, however, a costly operation since it consumes node and link resources excessively and often unnecessarily. There is no reason, for example, for a peer to receive a query message if the peer has no matching resource or is not on the path to a peer holding a matching resource. In this paper, we present a solution to this problem, which we call Route Learning, aiming to reduce query traffic in unstructured peer-to-peer networks. In Route Learning, peers try to identify the most likely neighbors through which replies can be obtained to submitted queries. in this way, a query is forwarded only to a subset of the neighbors of a peer, or it is dropped if no neighbor, likely to reply, is found. The scheme also has mechanisms to cope with variations in user submitted queries, like changes in the keywords. The scheme can also evaluate the route for a query for which it is not trained. We show through simulation results that when compared to a pure flooding based querying approach, our scheme reduces bandwidth overhead significantly without sacrificing user satisfaction. (C) 2008 Elsevier Ltd. All rights reserved
Data storage solutions for the federation of sensor networks
In the near future, most of our everyday devices will be accessible via some
network and uniquely identified for interconnection over the Internet. This
new paradigm, called Internet of Things (IoT), is already starting to influence
our society and is now driving developments in many areas.
There will be thousands, or even millions, of constrained devices that will
be connected using standard protocols, such as Constrained Application Protocol
(CoAP), that have been developed under certain specifications appropriate
for this type of devices. In addition, there will be a need to interconnect
networks of constrained devices in a reliable and scalable way, and federations
of sensor networks using the Internet as a medium will be formed.
To make the federation of geographically distributed CoAP based sensor
networks possible, a CoAP Usage for REsource LOcation And Discovery (RELOAD)
was recently proposed. RELOAD is a peer-to-peer (P2P) protocol that
ensures an abstract storage and messaging service to its clients, and it relies
on a set of cooperating peers that form a P2P overlay network for this purpose.
This protocol allows to define so-called Usages for applications to work
on top of this overlay network. The CoAP Usage for RELOAD is, therefore,
a way for CoAP based devices to store their resources in a distributed P2P
overlay. Although CoAP Usage for RELOAD is an important step towards
the federation of sensor networks, in the particular case of IoT there will be
consistency and efficiency problems. This happens because the resources of
CoAP devices/Things can be in multiple data objects stored at the overlay network,
called P2P resources. Thus, Thing resource updates can end up being
consuming, as multiple P2P resources will have to be modified. Mechanisms
to ensure consistency become, therefore, necessary.
This thesis contributes to advances in the federation of sensor networks by
proposing mechanisms for RELOAD/CoAP architectures that will allow consistency
to be ensured. An overlay network service, required for such mechanisms
to operate, is also proposed.Num futuro próximo, a maioria dos nossos dispositivos do dia-a-dia estarão
acessíveis através de uma rede e serão identificados de forma única para
poderem interligar-se através da Internet. Este novo paradigma, conhecido
hoje por Internet das Coisas (IoT), já está a começar a influenciar a nossa
sociedade e está agora a impulsionar desenvolvimentos em inúmeras áreas.
Teremos milhares, ou mesmo milhões, de dispositivos restritos que utilizarão protocolos padrão que foram desenvolvidos de forma a cumprir determinadas
especificações associadas a este tipo de dispositivos, especificações essas
que têm a ver com o facto destes dispositivos terem normalmente restrições
de memória, pouca capacidade de processamento e muitos possuirem limitações
energéticas. Surgirá ainda a necessidade de interligar, de forma fiável e
escalonável, redes de dispositivos restritos.(…
Locaware: Index Caching in Unstructured P2P-file Sharing Systems
International audienceThough widely deployed for file-sharing, unstructured P2P systems aggressively exploit network resources as they grow in popularity. The P2P traffic is the leading consumer of bandwidth, mainly due to search inefficiency, as well as to large data transfers over long distances. This critical issue may compromise the benefits of such systems by drastically limiting their scalability. In order to reduce the P2P redundant traffic, we propose Locaware, which performs index caching while supporting keyword search. Locaware aims at reducing the network load by directing queries to available nearby results. For this purpose, Locaware leverages natural file replication and uses topological information in terms of file physical distribution
Locaware: Index Caching in Unstructured P2P-file Sharing Systems
International audienceThough widely deployed for file-sharing, unstructured P2P systems aggressively exploit network resources as they grow in popularity. The P2P traffic is the leading consumer of bandwidth, mainly due to search inefficiency, as well as to large data transfers over long distances. This critical issue may compromise the benefits of such systems by drastically limiting their scalability. In order to reduce the P2P redundant traffic, we propose Locaware, which performs index caching while supporting keyword search. Locaware aims at reducing the network load by directing queries to available nearby results. For this purpose, Locaware leverages natural file replication and uses topological information in terms of file physical distribution
Dynamic data consistency maintenance in peer-to-peer caching system
Master'sMASTER OF SCIENC
Towards efficient peer-to-peer networks: A distributed cycle minimization approach
Master'sMASTER OF SCIENC
Exploiting Awareness of NetworkTopology and Relay Capability for P2PTVTraffic Localization
芝浦工業大学2016年
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