Transactional workloads have storage request streams consisting of many small, independent, random requests. Flash memory is well suited to these types of access patterns, but is not always cost-effective. This thesis presents a novel storage architecture called the SD Storage Array (SDSA), which adopts a many-device approach. It utilizes many flash storage devices in the form of an array of Secure Digital (SD) cards. This approach leverages the commodity status of SD cards to pursue a cost-effective means of providing the high throughput that transactional workloads require. Characterization of a prototype revealed that when the request stream was 512B randomly addressed reads, the SDSA provided 1.5 times the I/O operations per second (IOPS) of a top-of-the-line solid state drive, provided there were at least eight requests in-flight. A scale-out simulation showed the IOPS should scale with the size of the array, provided there are no upstream bottlenecks.

Transactional workloads have storage request streams consisting of many small, independent, random requests. Flash memory is well suited to these types of access patterns, but is not always cost-effective. This thesis presents a novel storage architecture called the SD Storage Array (SDSA), which adopts a many-device approach. It utilizes many flash storage devices in the form of an array of Secure Digital (SD) cards. This approach leverages the commodity status of SD cards to pursue a cost-effective means of providing the high throughput that transactional workloads require. Characterization of a prototype revealed that when the request stream was 512B randomly addressed reads, the SDSA provided 1.5 times the I/O operations per second (IOPS) of a top-of-the-line solid state drive, provided there were at least eight requests in-flight. A scale-out simulation showed the IOPS should scale with the size of the array, provided there are no upstream bottlenecks.

Recent Advancements in Solid State Memories have resulted in packing several Giga Bytes (GB) of memory into tiny postage stamp size Memory Cards. Of late, Secure Digital (SD) cards have become a de-facto standard for all portable handheld devices. They have found growing presence in almost all embedded applications, where huge volumes of data need to be handled and stored. For the very same reason SD cards are being widely used in space applications also. Using these SD Cards in space applications requires robust radiation hardened SD cards and Highly Reliable Fault Tolerant File Systems to handle them. The present work is focused on developing a Highly Reliable Fault Tolerant SD card based FAT16 File System for space applications.

"Forschung meets Business" - diese Kombination hat in den vergangenen Jahren immer wieder zu zahlreichen interessanten und fruchtbaren Diskussionen geführt. Mit dem Symposium "Sicherheit in Service-orientierten Architekturen" führt das Hasso-Plattner-Institut diese Tradition fort und lud alle Interessenten zu einem zweitägigen Symposium nach Potsdam ein, um gemeinsam mit Fachvertretern aus der Forschung und Industrie über die aktuellen Entwicklungen im Bereich Sicherheit von SOA zu diskutieren. Die im Rahmen dieses Symposiums vorgestellten Beiträge fokussieren sich auf die Sicherheitsthemen "Sichere Digitale Identitäten und Identitätsmanagement", "Trust Management", "Modell-getriebene SOA-Sicherheit", "Datenschutz und Privatsphäre", "Sichere Enterprise SOA", und "Sichere IT-Infrastrukturen". / 'Research meets Business' is the successful concept of the SOA Security Symposia held at the Hasso-Plattner-Institute that has lead to interesting discussions in the community. The SOA Security Symposium 2010 continued this tradition and invited researchers and representatives from the industry to discuss concepts, issues, and solution in the field of SOA Security. The topics presented in the scope of this symposium focused on the security related topics 'Secure Digital Identities and Identity Management', 'Trust Management', 'Model-driven SOA Security', 'Privacy',' Secure Enterprise SOA', and 'Secure IT-Infrastructures'.