Making Automated Testing of Cloud Applications an Integral Component of PaaS

Traditional testing is inadequate for the complexity of modern cloud application software stacks. While the platform-as-a-service (PaaS) model has streamlined application development and deployment, its multiple abstraction layers and dependencies have made testing more difficult. We argue that a modern PaaS offering should include a facility to thoroughly and automatically test a deployed cloud application with only little developer effort. To support this vision, we propose layered parameterized tests (LPTs) -- generalized integration tests suitable for cloud applications with multiple processing layers. From LPTs, a testing facility automatically generates concrete tests using layered symbolic execution, which focuses on exercising developer-written application logic instead of PaaS library code. We present our design of an automated testing system built on these concepts and demonstrate its use for a modern PaaS

High System-Code Security with Low Overhead

Security vulnerabilities plague modern systems because writing secure systems code is hard. Promising approaches can retrofit security automatically via runtime checks that implement the desired security policy; these checks guard critical operations, like memory accesses. Alas, the induced slowdown usually exceeds by a wide margin what system users are willing to tolerate in production, so these tools are hardly ever used. As a result, the insecurity of real-world systems persists. We present an approach in which developers/operators can specify what level of overhead they find acceptable for a given workload (e.g., 5%); our proposed tool ASAP then automatically instruments the program to maximize its security while staying within the specified "overhead budget." Two insights make this approach effective: most overhead in existing tools is due to only a few "hot" checks, whereas the checks most useful to security are typically "cold" and cheap. We evaluate ASAP on programs from the Phoronix and SPEC benchmark suites. It can precisely select the best points in the security-performance spectrum. Moreover, we analyzed existing bugs and security vulnerabilities in RIPE, OpenSSL, and the Python interpreter, and found that the protection level offered by the ASAP approach is sufficient to protect against all of them

Automated Debugging for Arbitrarily Long Executions

One of the most energy-draining and frustrating parts of software development is playing detective with elu-sive bugs. In this paper we argue that automated post-mortem debugging of failures is feasible for real, in-production systems with no runtime recording. We pro-pose reverse execution synthesis (RES), a technique that takes a coredump obtained after a failure and automat-ically computes the suffix of an execution that leads to that coredump. RES provides a way to then play back this suffix in a debugger deterministically, over and over again. We argue that the RES approach could be used to (1) automatically classify bug reports based on their root cause, (2) automatically identify coredumps for which hardware errors (e.g., bad memory), not software bugs are to blame, and (3) ultimately help developers repro-duce the root cause of the failure in order to debug it.

Operationalizing Co-Production in Public Services Delivery: The contribution of service blueprinting

We have argued for public services to move away from product-dominant logic towards a service approach. By taking a services orientation, the experience, inter-organizational, and systemic nature of public services delivery can be considered along with the role of the service user as a co-producer. In this article, we unpack how co-production can be operationalized through the application of service blueprinting. This article presents an example within higher education where the creation of a blueprint brought together staff and students to focus on the design of student enrolment, resulting in improved student experience and supporting co-production

Genome Sequence of Fusobacterium nucleatum Subspecies Polymorphum — a Genetically Tractable Fusobacterium

Fusobacterium nucleatum is a prominent member of the oral microbiota and is a common cause of human infection. F. nucleatum includes five subspecies: polymorphum, nucleatum, vincentii, fusiforme, and animalis. F. nucleatum subsp. polymorphum ATCC 10953 has been well characterized phenotypically and, in contrast to previously sequenced strains, is amenable to gene transfer. We sequenced and annotated the 2,429,698 bp genome of F. nucleatum subsp. polymorphum ATCC 10953. Plasmid pFN3 from the strain was also sequenced and analyzed. When compared to the other two available fusobacterial genomes (F. nucleatum subsp. nucleatum, and F. nucleatum subsp. vincentii) 627 open reading frames unique to F. nucleatum subsp. polymorphum ATCC 10953 were identified. A large percentage of these mapped within one of 28 regions or islands containing five or more genes. Seventeen percent of the clustered proteins that demonstrated similarity were most similar to proteins from the clostridia, with others being most similar to proteins from other gram-positive organisms such as Bacillus and Streptococcus. A ten kilobase region homologous to the Salmonella typhimurium propanediol utilization locus was identified, as was a prophage and integrated conjugal plasmid. The genome contains five composite ribozyme/transposons, similar to the CdISt IStrons described in Clostridium difficile. IStrons are not present in the other fusobacterial genomes. These findings indicate that F. nucleatum subsp. polymorphum is proficient at horizontal gene transfer and that exchange with the Firmicutes, particularly the Clostridia, is common

Energy In/Out of Place

This book, and the online workshop that preceded it, are attempts to intensify the sense of place within our scholarship and in our scholarly practices. They are formed from the efforts of five research teams examining energy cultures in five different locations around the world. Team members weren’t necessarily experts on their given places, but many were bound to these sites through time, kith, and kin

The Influence of Technological Knowledge Base and Organizational Structure on Technology Collaboration

This study investigates how an incumbent company's internal characteristics influence its propensity to form learning alliances. A firm may be reluctant to enter a research alliance when it has deep knowledge in a certain technological field due to concerns about knowledge leakage and the low possibility of being able to learn much from collaboration. On the contrary, when the firm has a broad knowledge base, it may have high propensity to enter alliances due to more self-confidence in its ability to learn fast from partners. In addition, we argue that when a firm concentrates its R&D at a central location, this neutralizes the positive and negative influences of the two knowledge base features on alliance formation. We tested and found support for the hypotheses using a database of 1550 alliances undertaken by 78 large incumbent pharmaceutical, chemical, and agro-food companies active in the biotechnology sector during 1993–2002