Securely sharing and managing personal content is a challenging task in multi-device environments. In this paper, we design and implement a new platform called personal content networking (PCN). Our work is inspired by content-centric networking (CCN) because we aim to enable access to personal content using its name instead of its location. The unique challenge of PCN is to support secure file operations such as replication, updates, and access control over distributed untrusted devices. The primary contribution of this work is the design and implementation of a secure content management platform that supports secure updates, replications, and fine-grained content-centric access control of files. Furthermore, we demonstrate its feasibility through a prototype implementation on the CCNx skeleton.
: Wide area P2P storage can be classified based on the overlay structure: (1) a structured system (e.g. PAST @cite_21 , CFS, Ivy) forms a structured overlay network using a distributed hash table (DHT), and (2) a structure-less scheme (e.g. Gnutella and eDonkey) forms a structure-less overlay network where the overlay links are arbitrarily established. Unlike unstructured P2P networks, DHTs provide better performance for searching for items over a large number of distributed nodes, and they have been widely adopted to implement wide area P2P storage. Most P2P storage systems assume wired Internet scenarios and support strong consistency, which is less suitable for personal content networking. As a recent work, Plethora focuses on semi-static peers with strong network connectivity and a partially persistent network state. In a semi-static P2P network, peers are likely to remain participants in the network over long periods of time (e.g., compute servers), and are capable of providing reasonably high availability and response-time guarantees @cite_2 .
@cite_21 @cite_2
1502216169 1558940048 2121531691 2049794981
Trends in conventional storage infrastructure motivate the development of foundational technologies for building a wide-area read-write storage repository capable of providing a single image of a distributed storage resource The overarching design goals of such an infrastructure include client performance, global resource utilization, system scalability (providing a single logical view of larger resource and user pools) and application scalability (enabling single applications with large resource requirements) Such a storage infrastructure forms the basis for second generation data-grid efforts underlying massive data handling in high-energy physics, nanosciences, and bioinformatics, among others. This paper describes some of the foundational technologies underlying such a repository, Plethora, for semi-static peer-to-peer (P2P) networks implemented on a wide-area Internet testbed In contrast to many current efforts that focus entirely on unstructured dynamic P2P environments, Plethora focuses on semi-static peers with strong network connectivity and a partially persistent network state In a semi-static P2P network, peers are likely to remain participants in the network over long periods of time (e.g., compute servers), and are capable of providing reasonably high availability and response-time guarantees The repository integrates novel concepts in locality enhancing overlay networks, transactional semantics for read-write data coupled with hierarchical versioning, and novel erasure codes for robustness While mentioning approaches taken by Plethora to other problems, this paper focuses on the problem of routing data request to blocks, while integrating caching and locality enhancing overlays into a single framework We show significant performance improvements resulting from our routing techniques. In this paper, we address the problem of designing a scalable, accurate query processor for peer-to-peer filesharing and similar distributed keyword search systems. Using a globally-distributed monitoring infrastructure, we perform an extensive study of the Gnutella filesharing network, characterizing its topology, data and query workloads. We observe that Gnutella's query processing approach performs well for popular content, but quite poorly for rare items with few replicas. We then consider an alternate approach based on Distributed Hash Tables (DHTs). We describe our implementation of PIERSearch, a DHT-based system, and propose a hybrid system where Gnutella is used to locate popular items, and PIERSearch for handling rare items. We develop an analytical model of the two approaches, and use it in concert with our Gnutella traces to study the trade-off between query recall and system overhead of the hybrid system. We evaluate a variety of localized schemes for identifying items that are rare and worth handling via the DHT. Lastly, we show in a live deployment on fifty nodes on two continents that it nicely complements Gnutella in its ability to handle rare items. Over the Internet today, computing and communications environments are significantly more complex and chaotic than classical distributed systems, lacking any centralized organization or hierarchical control. There has been much interest in emerging Peer-to-Peer (P2P) network overlays because they provide a good substrate for creating large-scale data sharing, content distribution, and application-level multicast applications. These P2P overlay networks attempt to provide a long list of features, such as: selection of nearby peers, redundant storage, efficient search location of data items, data permanence or guarantees, hierarchical naming, trust and authentication, and anonymity. P2P networks potentially offer an efficient routing architecture that is self-organizing, massively scalable, and robust in the wide-area, combining fault tolerance, load balancing, and explicit notion of locality. In this article we present a survey and comparison of various Structured and Unstructured P2P overlay networks. We categorize the various schemes into these two groups in the design spectrum, and discuss the application-level network performance of each group. Distributed hash table (DHT) systems are an important class of peer-to-peer routing infrastructures. They enable scalable wide-area storage and retrieval of information, and will support the rapid development of a wide variety of Internet-scale applications ranging from naming systems and file systems to application-layer multicast. DHT systems essentially build an overlay network, but a path on the overlay between any two nodes can be significantly different from the unicast path between those two nodes on the underlying network. As such, the lookup latency in these systems can be quite high and can adversely impact the performance of applications built on top of such systems.In this paper, we discuss a random sampling technique that incrementally improves lookup latency in DHT systems. Our sampling can be implemented using information gleaned from lookups traversing the overlay network. For this reason, we call our approach lookup-parasitic random sampling (LPRS). LPRS is fast, incurs little network overhead, and requires relatively few modifications to existing DHT systems.For idealized versions of DHT systems like Chord, Tapestry and Pastry, we analytically prove that LPRS can result in lookup latencies proportional to the average unicast latency of the network, provided the underlying physical topology has a power-law latency expansion. We then validate this analysis by implementing LPRS in the Chord simulator. Our simulations reveal that LPRS-Chord exhibits a qualitatively better latency scaling behavior relative to unmodified Chord.Finally, we provide evidence which suggests that the Internet router-level topology resembles power-law latency expansion. This finding implies that LPRS has significant practical applicability as a general latency reduction technique for many DHT systems. This finding is also of independent interest since it might inform the design of latency-sensitive topology models for the Internet.