The EMI Grid Middleware The EMI Grid Middleware

The European Middleware Initiative (EMI) project aims to deliver a consolidated set of middleware products based on the four major middleware providers in Europe - ARC, dCache, gLite and UNICORE.   The products, managed in the past by these separate providers, and now developed, built and tested in collaboration, are for deployment in EGI (as part of the Unified Middleware Distribution or UMD), and other distributed computing infrastructures, extend the interoperability and integration between grids and other computing infrastructures, strengthen the reliability and manageability of the services and establish a sustainable model to support, harmonise and evolve the middleware, ensuring it responds effectively to the requirements of the scientific communities relying on it.

Project objectives

  1. Simplify and organize the different middleware services implementations by delivering a streamlined, coherent, tested and standard compliant distribution able to meet and exceed the requirements of EGI and other distributed computing infrastructures and their user communities.
  2. Increase the interoperability, manageability, usability and efficiency of the services by developing or integrating new functionality as needed following existing and new requirement of EGI and other infrastructures and their user communities.
  3. Support efficient, reliable operations of EGI and other infrastructures by reactively and proactively supporting and maintaining the middleware distribution and providing users with increasingly user-friendly, maintainable, reliable, stable, and scalable software.
  4. Strengthen the participation and support for user communities in the definition and evolution of middleware services by promoting the EMI achievements, objectives and plans, and move the EMI middleware towards a more sustainable model by expanding the collaboration with national and international research agencies, scientific research programs and with industrial providers.

EMI 1 (codename Kebnekaise) is the first step towards a stable integrated distribution of compute and data management services that will deliver a broad suite of technologies for deployment in distributed computing infrastructures in Europe and beyond.

The first EMI release is focused primarily on laying the foundations for the distribution, increasing the level of integration among the original middleware stacks, improving the compatibility with mainstream operating systems' guidelines and extending the compliance with existing standards.

EMI 1 components follow more closely packaging guidelines and policies defined by Fedora, introduce widespread compliance with the File Hierarchy Standard (FHS), make extensive use of off-the-shelf packages from the OS distribution or major downstream repositories like EPEL, reduce the dependency on less standard technologies and protocols.

EMI 1 introduces a number of changes and new functionality in response to existing user requirements. The major highlights are:

  • Security - Replacement of GSI with SSL in the security components, most notably VOMS; REST-based interface for obtaining X.509 attribute certificates in VOMS Admin; initial integration of ARGUS with middleware services (e.g. CREAM)
  • Compute - Full support for the CLUSTER service in CREAM; initial support for GLUE 2 in all CEs; integration of ARGUS in CREAM; initial implementation of common MPI methods across the different compute services
  • Data - Adoption of pNFS4.1 and WebDAV standards (dCache); preview version of a messaging-based Storage Element-File Catalog synchronization service (SEMsg)
  • Information Systems - ARC CE, UNICORE WS, CREAM, dCache, DPM expose a richer set of information via the experimental adoption of the GLUE2 information model standard.