GSC Sentinel-2 PDGS STBD - emits - ESA

Local Area NetworkGSC Sentinel-2 PDGS STBDIssue 1 Revision 2 (draft) - 25.07.2010GMES-GSEG-EOPG-TN-09-0031page 53 of 60It allows the interconnection between the servers of the different units or subsystems, i.e.:o The exchanges between the servers of the computer clustero The exchanges between the operator terminals and the computer cluster,It allows also the links with the centre infrastructure (from dislocated operator terminals) andthe exchanges between different centres.Computer clusterIt is a BladeCenter comprising several server-blades. The frame offer to servers theinterconnection resources they need (network, supply).These blades have identical material characteristics and they are allocated:o Statically at one subsystem start - one blade having the opportunity of hosting severalsubsystems,o Dynamically for image processing algorithms.Up-to-date information about the computation power of the most recent hardwareconfiguration can be found on the website SPEC.org.Benchmarked values presented in chapter 4 have been estimated using IBM BladeCenterHS21 (Intel Xeon E5430) which has come out in winter 2008 (Base: 21.1, peak: 24.1Mflops). The latest Blade Center dating summer 2009 has much higher performancesassuring for example a base value 36.3 Mflops and a peak value of 38.9 Mflops (IBMBladeCenter HS22 (Intel Xeon X5560)).Furthermore, better processing time can be expected thanks to technological evolutions.Storage Area NetworkIt allows the computer cluster servers to access via a Fibre Channel network to remotecomputer storage devices (such as disk arrays, tape libraries) as if these devices werelocally attached to the operating system (in terms of data rate I/O). Each server has an HBAcard allowing it to access to the disk volumes which are shared with the other servers.Disk arraysThe disk array hosts unit or subsystem data. These disks have a RAID array configurationoffering both redundancy and the performances needed for supporting the required I/Orates. Volumes are shared between servers via a high performance clustered file system.Storage capacities are dimensioned according to each centre needs.Archive and backup meansThey can be composed of a LTO libraries exclusively used by the archive subsystem and bythe subsystem charged of the backup. This library is managed by a server that is external tothe integrated computer cluster.Storage capacities are dimensioned according to each centre needs.ESA UNCLASSIFIED – For Official Use© ESAThe copyright of this document is the property of ESA. It is supplied in confidence and shall not be reproduced, copied orcommunicated to any third party without written permission from ESA.