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Topic I: Demand Addressable Network

(a) Demand Interpreter

Technology that interprets user’s abstract demands instantaneously, and expands them into a combination of concrete sub-demands. A user’s demand is to be interpreted into simple parameter combinations, which are divided into three elements, “When”, “Where” and “What”. For example, the user’s demand, “the possibility of an outbreak of fire within a 10 km radius from this location,” is expanded into the following parameters;
((When, Now), (Where, Here < 10 km), (What, Temperature = Quickly Rising)). Likewise, the demand, “the possibility of a fire within two days and within a 5 km radius to the north of this location,” is expanded into the following; ((When, Now > 2 day), (Where, ((Here < 5 km) & North), (What, Temperature = Rapid-up)). Information that we expect will be included in demands - parameters, reserved words and other related keywords - is prepared in table format. The interpreter reads the table on startup, and it can be easily expanded at any time by updating the contents of the table.

(b) Demand Addressing

Technology that dynamically finds the resources which hold the desired sensing data within the network’s sensors and local DBs, etc., through the use of expanded sub-demands or a combination of them without referring to any centrally-managed directories or other resources. We attempt to apply Distributed Hash Table technology (DHT), which is used by Peer-to-Peer (P2P) technology. The search keys to be stored in the DHT, however, are not simple file names as in P2P technology, but conditions or logical expressions expanded by the above-mentioned demand interpreter. We expect additional system enhancement is required in order to make our attempt work properly.

(c) Data Mash-up Network

Technology that combines (mashes up) the acquired data in the network, and displays it to the user. We use a messaging network technology, which we already hold, as a base architecture. The messaging network (MN) is a technology to construct the overlay-network by using XML routers and the Gateways. MN has realized a content-based data transfer mechanism on the overlay-network, by unit of the message described in XML. The Gateway dynamically converts received local data into the XML-format message. The message is transferred up to a target terminal through the XML routers that have an XML interpretation function. The basic component of our research goal, an in-network data mash-up function, is already realized since the XML router can also mash up data as the need arises [9]. However, there are new issues to be resolved: integration with a resource finding mechanism through DHT technology, to be realized by I- (b); and analysis of the method by which we may efficiently implement a mutual conversion function for local data and XML-format messages which will then be incorporated into the Gateway arranged at the contact point with each sensor network and service system.

[9] T. Hayashi, H. Fukuhara, M. Hisada, K. Suzuki, T. Yamada, Y. Watanabe, J. Terazono, T. Suzuki, T. Miyazaki, S. Saito, I. Koseda, and J. Iwase, “A network-centric approach to sensor-data and service integration,” Proc. SICE Annual Conference 2011, pp. 2037-2042, 2011.