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Efficient information sharing in peer-to-peer environment |
Efficient information sharing in peer-to-peer environment |
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Efficient resource discovery is an essential problem in peer-to-peer networks because there is |
Efficient resource discovery is an essential problem in Peer-to-Peer networks because there is |
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no centralized index where to look for information about resources. There are two well known |
no centralized index where to look for information about resources. There are two well known |
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approaches in which all modern Peer-to-Peer systems fall: the loosely structured approach |
approaches in which all modern Peer-to-Peer systems fall: the loosely structured approach |
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and the tightly structured approach. In the loosely structured approach the construction |
and the tightly structured approach [hyytiala03stormp2p]_. In the loosely structured approach the |
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and the maintenance of the network is controlled loosely while tightly structured approach |
construction and the maintenance of the network is controlled loosely. In the loosely structured approach, |
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t he performance of resource discovery is $O(n)$ and the number of network packets can grow with |
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$O(n^{2})$, where $n$ is the number of participating nodes in the network. Tightly structured approach |
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is constructed deterministically, which all participating peers have to follow; the topology of the |
is constructed deterministically, which all participating peers have to follow; the topology of the |
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overlay and the placement of services is controlled tightly. Currently either of the approches |
overlay and the placement of services is controlled tightly. This feafure provides $O(\log{n})$ |
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do not support *both* adaptable and efficient resource discovery in peer-to-peer environment. |
resource discovery efficiency and the number of packets grow with $O(\log{n})$. However, |
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the tightly structured approach may not be reliable in highly adverse conditions, such as |
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In our research, we |
sudded network partition or wide hostile attack. Thus, either of the approches do not support |
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*both* adaptable and efficient resource discovery in peer-to-peer environment. |
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Currently we use distributed hash tables for searching blocks |
In our research, we focus on developing algorithms which are both adaptable and efficient in highly |
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in a distributed environment, but the use of other Peer-to-Peer technologies are |
adverse conditions. Specifically, we study if we can combine the adaptivity of the loosely |
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also studied. |
structured approach with the efficiently of the tightly structured approach. We also examine |
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how well distributed resource discovery algorithms can be made to endurate hostile attacks |
610 |
Research on how location-independent identifiers can be used to find |
in Peer-to-Peer enviroment. |
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information in a Peer-to-Peer environment. To support our research work, we have |
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developed a software library, named as Storage Modules (Storm), which provides |
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the basis for storing (xanalogical) data to our system. Storm provides an alternative to |
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traditional file-based storage as all data is stored as immutable *blocks*. A block is |
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like a file but it cannot be changed, and instead of a file name it is identified by a |
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SHA-1 cryptographic content hash [fips-sha-1]_. Thus, identifiers are |
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location-independent and globally unique. |
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Research focuses on finding efficient methods for locating xanalogical media |
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using location-independent and globally unique identifiers from the Peer-to-Peer |
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network. Currently we use distributed hash tables for searching blocks |
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in a distributed environment, but the use of other Peer-to-Peer technologies are |
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also studied. |
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.. more about theories behind the p2p stuff (HH) |
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Our goal is to build a Peer-to-Peer system that allows one to perform a *global* |
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data lookups and fetch a block if *anybody* has published it in the Internet. |
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Flexible focus+context views such as fisheye distortions |
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allow more context to be shown but also induce |
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usability issues that need to be solved. |
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612 |
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613 |
Research schedule |
Research schedule |