Dirac Lightweight Information and Monitoring Services Using XML-RPC and Instant Messaging

This paper presents recent work on a scalable, lightweight approach for distributed information and monitoring systems done for the LHCb experiment's DIRAC grid software package. Two complementary systems are presented, one based on a layered, DNS-like information service, and the other a monitoring mechanism using instant messaging for ad hoc networks which are formed in a grid environment. The paper outlines the requirements, design architecture and features of the implementation. The performance results of these two systems in the recent LHCb 2004 Data Challenge are presented.