1. CLRC and the European DataGrid Middleware Information and Monitoring Services The current information service is built on the hierarchical database OpenLDAP (lightweight directory access protocol) as provided by Globus’s Metacomputing Directory Service The information published relates to the resources available at a site This information is used by the resource broker for resource discovery and job scheduling computing element storage elements that are close (not necessarily at the same site) status supported protocols file statistics network information between this and other sites storage element Example output from the RIPE NCC TTM box Resource Broker Storage Element - A Computing Element - A Information and Monitoring Services Replica Catalogue Job Submission UI JDL Network Monitoring - A Computing Element - B Storage Element - B Network Monitoring - B User Virtual Organisation 1 (Experiment 1) Middle Layer MSM Interface Network API Grid FTPNFSRFIO Storage Element Applications Physical Fabric Middleware Information and Monitoring Services HEP AppsEO AppsBio Apps Workload Management Data Management Globus Middleware NetworkingComputing FabricMass Storage CLRC/PPARC participation Relational Grid Monitoring Architecture R-GMA is being developed within the Information and Monitoring Services work package as a new information and monitoring system infrastructure R-GMA consists of Consumers, Producers and a directory service (the Registry) Producers register with the registry and describe the type and structure of information they want to make available to the Grid Consumers query the registry to find out what type of information is available and locate producers that provide such information The consumer can contact the producer directly to obtain the relevant data Red indicates CLRC leadership/management of the work package/group Mass Storage Management Network Services Virtual Organisation 3 (Experiment 3) Virtual Organisation 2 (Experiment 2) Network Services One machine per testbed site is used for network monitoring Both active and passive measurements are made The information is published via the information service and will be used by the resource broker for job scheduling Measurements include: packet loss one-way delay round trip time (RTT) jitter RTT variation DataGrid Security Grid certificates enable single sign on to the grid Grid certificates issued by certificate authorities Each site has a list of trusted authorities Developing systems for grid wide authentication and authorisation Architecture Task Force The ATF was created to define an architecture for the DataGrid It is composed of one person from each of the middleware work packages and invited experts The architecture documents define a set of services and their interdependencies It has been an important contribution to the success of the first testbed Storage Element The Storage Element is an integration project between grid communication protocols and a diversity of mass storage systems The Storage Element facilitates centralised brokering of resources via location independent interfaces The Storage Element is divided into three layers Client Applications Virtual Organisations A virtual organisation is a dynamic collection of individuals, institutions, and resources with a set of sharing rules that clearly and carefully define what is shared, who is allowed to share, and the conditions under which sharing occurs A site may have resources that are allocated to one or more virtual organisation Middleware Middleware provides the interface between the applications and the physical fabric CLRC/PPARC and the DataGrid Project CLRC staff, and PPARC staff based at RAL, are active in a number of DataGrid work packages Particle Physics Applications Information and Monitoring Services Mass Storage Management Testbed Integration Network Services Fabric Management Invocation Information Registry Interface Registry Servlet Schema Interface Schema Servlet Client side Circular Buffer Producer Servlet Consumer Servlet Consumer Archiver Servlet Hidden components Data Base Producer Servlet Archiver Data Base Producer Circular Buffer Producer Sensor Application The Producer Consumer Model Architectural Task Force Security Co-ordination Group UK DataGrid Co-ordination Testbed Certificate Authorities group