Demonstration: Active Asynchronous Transaction Management in High-Autonomy Federated Environment Using Data Agents: Global Change Master Directory v8.0

This demonstration focuses on the implementation of an asynchronous transaction protocol [1,6, 8] which satisfies the requirement of replicating DlF entries through the internet across continents in the International Directory Network (IDN). We have designed a Primary Site Distribution protocol which is asynchronous but active i.e. participating sites in the network announce the arrival of new data to other sites in the network. This protocol also addresses the issues involved in dual ownership of entries which is a challenge that faces several emerging distributed transaction management systems [3,4,8]. Abstract The Global Change Master Directory (GCMD) is an earth scie ce information repository that specifically tracks rese rch data on global climatic change. Building a dire tory of Earth science metadata that allows the exc ange of metadata content among partner org nizations is challenging due to the complex issues inv ved in supporting heterogeneous metadata schema, dat base schema, database implementation and platforms. Thi dem{Jnstration presents the design of the MD8 (Ma ter Directory v8.0), which allows automated exc ange of metadata content among earth science coIl borators through a proposed asynchronous dis ibuted transaction protocol. Specifically, the dem nstration will focus on the Local Data Agent (LDA) that captures local database updates and broadcasts them to ther cooperating nodes asynchronously using an Ann uncer. The objective of the new system (MD8) is to promote the current architecture of the GCMD from a client-server architecture to a federated architecture that is totally automated while providing sites participating in the IDN network with the autonomy needed to maintain their local systems. A detailed overview of the design of the MD8 is included in [9].