Data-Centric Storage in Sensornets with GHT, a Geographic Hash Table
Title | Data-Centric Storage in Sensornets with GHT, a Geographic Hash Table |
Publication Type | Journal Article |
Year of Publication | 2003 |
Authors | Ratnasamy, S., Karp B., Shenker S. J., Estrin D., Govindan R., Yin L., & Yu F. |
Volume | 8 |
Issue | 4 |
Page(s) | 427-442 |
Other Numbers | 202 |
Abstract | Making effective use of the vast amounts of data gathered by large-scale sensor networks (sensornets) will require scalable, self-organizing, and energy-efficient data dissemination algorithms. For sensornets, where the content of the data is more important than the identity of the node that gathers them, researchers have found it useful to move away from the Internet's point-to-point communication abstraction and instead adopt abstractions that are more data-centric. This approach entails naming the data and using communication abstractions that refer to those names rather than to node network addresses [1,11]. Previous work on data-centric routing has shown it to be an energy-efficient data dissemination method for sensornets [12]. Herein, we argue that a companion method, data-centric storage (DCS), is also a useful approach. Under DCS, sensed data are stored at a node determined by the name associated with the sensed data. In this paper, we first define DCS and predict analytically where it outperforms other data dissemination approaches. We then describe GHT, a Geographic Hash Table system for DCS on sensornets. GHT hashes keys into geographic coordinates, and stores a keyvalue pair at the sensor node geographically nearest the hash of its key. The system replicates stored data locally to ensure persistence when nodes fail. It uses an efficient consistency protocol to ensure that keyvalue pairs are stored at the appropriate nodes after topological changes. And it distributes load throughout the network using a geographic hierarchy. We evaluate the performance of GHT as a DCS system in simulation against two other dissemination approaches. Our results demonstrate that GHT is the preferable approach for the application workloads we analytically predict, offers high data availability, and scales to large sensornet deployments, even when nodes fail or are mobile. |
Bibliographic Notes | ACM Mobile Networks and Applications (MONET), Vol. 8, No. 4, pp. 427-442 |
Abbreviated Authors | S. Ratnasamy, B. Karp, S. Shenker, D. Estrin, R. Gvoindan, L. Yin, and F. Yu |
ICSI Research Group | Networking and Security |
ICSI Publication Type | Article in journal or magazine |