Building secure protocols for extensible distributed coordination through secure extensions

Mechanisms for distributed coordination are used in the development of many distributed systems and, generally, are implemented on top of coordination infrastructures, such as tuple spaces. Although tuple spaces provide the coordination functionalities, a recent study showed that extensibility is fundamental for performance. The main idea behind extensibility is to allow the servers, supporting the coordination infrastructure, to access and process coordination information. Consequently, it is not necessary to move information from servers to clients or to reprocess requests due to concurrency. Unfortunately, existing proposals for extensible distributed coordination do not provide security and privacy once servers access data in plaintext. This work uses robust cryptographic schemes recently integrated into DepSpace, a tuple space implementation, to propose secure protocols for coordination with and without extensions. Experiments compare the proposed solutions and consider also the proposed protocols without security and privacy, showing that extensible coordination significantly improves system performance even using costly cryptographic operations.