Resilient Architecture Research Articles

An ultra-low power resilient multi-core architecture with static and dynamic tolerance to ambient temperature-induced variability

Near-threshold operation is today a key research area in Ultra-Low Power (ULP) computing, as it promises a major boost in energy efficiency compared to super-threshold computing and it mitigates thermal bottlenecks. Unfortunately near-threshold operation is plagued by greatly increased sensitivity to threshold voltage variations, such as those caused by ambient temperature fluctuation. In this paper we focus on a tightly-coupled ULP processor cluster architecture where a low latency, high-bandwidth processor-to-L1-memory interconnection network plays a key role. We propose an architectural scheme to tolerate ambient temperature-induced variations capable of statically (off-line) and dynamically (on-line) adapting the processor-to-L1-memory latency without compromising execution correctness. We extensively tested our solution in different scenarios and we evaluated the different design trade-offs, showing the cost, performance and reliability gain compared to state-of-the-art static solutions. The dynamic solution, thanks to its lightweight runtime overhead, outperforms the static solution and is able to reach a performance gain up to 25% in a typical use case scenario with a very low (<4%) area overhead.

Multi-stratum resources resilience in software defined data center interconnection based on IP over elastic optical networks

IP over elastic optical network is a very promising networking architecture to interconnect data centers. It can enable efficient resource utilization and support heterogeneous bandwidth demands in cost-effective, highly available, and energy-effective manner. In case of aggregation elastic optical network node failure, to ensure a high-level quality of service for user request after the failure becomes a research focus. In this paper, we present a novel multi-stratum resources resilience (MSRR) architecture for the data center services in software defined data center interconnection based on IP over elastic optical networks. The MSRR can enable joint optimization of IP network, elastic optical network, and application stratum resources, and enhance the service resilience and the data center responsiveness to the dynamic end-to-end service demands. Additionally, a service-aware resource collaborative resilience strategy for MSRR is introduced based on the proposed architecture, which can provide the restoration using the multiple stratums resources in case of failure. The overall feasibility and efficiency of the proposed architecture are experimentally verified on our testbed. Moreover, the network performances are quantitatively evaluated through the simulation under heavy traffic load scenario in terms of path blocking probability, resource occupation rate, and path resilience latency.

ARQUITECTURA RESISTENTE DETERMINANTE DEL LIDERAZGO PEDAGÓGICO EN LOS CENTROS DE EDUCACIÓN SECUNDARIA

INTRODUCCION. Las recientes aportaciones en el campo del liderazgo pedagogico destacan la necesidad de prestar atencion a la actuacion del director escolar, pues es un elemento clave para conseguir una comunidad dentro de la escuela dirigida a la mejora del aprendizaje de los alumnos. METODO. En este articulo analizamos la practica diaria de 24 directores de Institutos de Educacion Secundaria de la provincia de Granada (Espana), con el objeto de describir la actuacion de los directores en sus tareas de liderazgo pedagogico y profundizar en los procesos que utilizan para la construccion de un contexto facilitador del aprendizaje. Para recoger la tarea del director utilizamos un �guion de auto-observacion� que cada director participante en la investigacion rellena de manera independiente a lo largo de dos semanas durante el curso academico 2011-2012. En este guion de auto-observacion cada director participante en la investigacion recoge informacion diariamente sobre el tipo de tarea realizada, el tiempo dedicado a cada tarea, el lugar de realizacion de la tarea y las emociones positivas y negativas que les producen la realizacion de las distintas tareas llevadas a cabo a lo largo del dia. RESULTADOS y DISCUSION. El trabajo aporta datos significativos acerca de la �arquitectura resistente� que determina el contexto espacial/emocional donde el director intenta llevar a cabo sus funciones de liderazgo pedagogico, una informacion esencial que puede ser utilizada para la transformacion del contexto en el que el director de educacion secundaria lleva a cabo su tarea directiva y para la mejora de sus condiciones de trabajo.

What Will the Architect Be Doing Next? How is the profession of the architect evolving as the focus of society shifts from sustainability to resilience or reactivist-driven design demands?

A more engaging and visionary role for architects is emerging, altering focus from a technological advisor to a more sociological engineer or entrepreneur. By researching a selection of current architectural practices an attempt is made to describe this evolution of the architect’s role and to assess if this is truly a new development or even a paradigm shift. Based upon on an analysis of texts by scholars and written conversations with architects on the subject of sustainable architecture, resilient architecture, agency in architecture and reactivist architecture, supplemented with additional statements by architects on the matter of architectural practice, an evolution of this role made clear and put into perspective. The aim of this review therefore is to distil some kind consensus within architectural practice of how the architect’s role is to evolve in the foreseeable future. It appears that reactivist architecture as a descriptive set of principles has absorbed elements of all of the above, becoming more than the sums of its parts and allowing for a new role for the architect to emerge.

What Will the Architect Be Doing Next? How is the profession of the architect evolving as the focus of society shifts from sustainability to resilience or reactivist-driven design demands?

A more engaging and visionary role for architects is emerging, altering focus from a technological advisor to a more sociological engineer or entrepreneur. By researching a selection of current architectural practices an attempt is made to describe this evolution of the architect’s role and to assess if this is truly a new development or even a paradigm shift. Based upon on an analysis of texts by scholars and written conversations with architects on the subject of sustainable architecture, resilient architecture, agency in architecture and reactivist architecture, supplemented with additional statements by architects on the matter of architectural practice, an evolution of this role made clear and put into perspective. The aim of this review therefore is to distil some kind consensus within architectural practice of how the architect’s role is to evolve in the foreseeable future. It appears that reactivist architecture as a descriptive set of principles has absorbed elements of all of the above, becoming more than the sums of its parts and allowing for a new role for the architect to emerge.

Performance Analysis of Resilient FTTH Architecture with Protection Mechanism

Fiber-To-The-Home [FTTH] is an alternate technology for broadband access networks. Passive optical network (PON) is considered the most promising solution due to the relatively low deployment cost. Current time division multiplexing [TDM] PON architectures are economically feasible, are band limited. The WDM PONs currently available offers enough bandwidth for the present and also for future multimedia broadband services. The purpose of this paper is to simulate resilient access network architecture with a cable route protection function based on hybrid wavelength division multiplexing and time division multiplexing passive optical network (WDM/TDM-PON) systems. Hybrid WDM-TDM PON combines the advanced features of both TDM PON and WDM PON. The reuse of existing optical fiber cable networks allows the introduction of duplicate routes for the shared portions of PONs by using a few optical fiber cables with simple structures. In this work, the hybrid WDM/TDM PON based Ladder network is simulated and the transmission characteristics evaluated. Simulation is done by using Optsim ver.5.3.

Rafhyc: an Architecture for Constructing Resilient Services on Federated Hybrid Clouds

Federated hybrid clouds is a model of service access and delivery to community cloud infrastructures. This model opens an opportunity window to allow the integration of the enhanced science (eScience) with the Cloud paradigm. The eScience is computationally intensive science that is carried out in highly distributed computing infrastructures. Nowadays, the eScience big issue on Cloud Computing is how to leverage on-demand computing in scientific research. This requires innovation at multiple levels, from architectural design to software platforms. This paper characterizes the requirements of a federated hybrid cloud model of Infrastructure as a Service (IaaS) to provide eScience. Additionally, an architecture is defined for constructing Platform as a Service (PaaS) and Software as a Service (SaaS) in a resilient manner over federated resources. This architecture is named Rafhyc (for Resilient Architecture of Federated HYbrid Clouds). This paper also describes a prototype implementation of the Rafhyc architecture, which integrates an interoperable community middleware, named DIRAC, with federated hybrid clouds. In this way DIRAC is providing SaaS for scientific computing purposes, demonstrating that Rafhyc architecture can bring together eScience and federated hybrid clouds.

Cross stratum resilience for OpenFlow-enabled data center interconnection with Flexi-Grid optical networks

Nowadays, most of the service providers offer their services and support their applications through federated sets of data centers, which needs to be interconnected using high-capacity telecom transport networks. To provide such high-capacity network channels, data center interconnection is typically based on Flexi-Grid optical networks that ensure the performance guarantee of low delay, high availability and robustness at a low cost. In case of natural disasters, to ensure a high-level quality of service (QoS) for user request after disasters becomes a research focus. In this paper, we present a novel cross stratum resilience (CSR) architecture for OpenFlow-enabled data center interconnection with Flexi-Grid optical networks. The proposed architecture can enable joint optimization of optical networks and application stratum resources, and enhance the service resilience and the data center responsiveness to end-to-end service demands. Based on this architecture, the data center service deployment (DCSD) strategy is proposed to solve the data center services pre-allocation problem. Additionally, the data center resource maintenance (DCRM) strategy is introduced based on the proposed architecture to describe data center resource occupation for choosing the backup server as the alternative destination. The overall feasibility of these strategies is experimentally validated and the network performances are quantitatively evaluated on our large scale testbed with 200 virtual OpenFlow-enabled nodes.

Self-Adapting Resource Escalation for Resilient Signal Processing Architectures

To deal with susceptibility to aging and process variation in the deep submicron era, signal processing systems are sought to maintain quality and throughput requirements despite the vulnerabilities of the underlying computational devices. The Priority Using Resource Escalation (PURE) online resiliency approach is developed herein to maintain throughput quality based on the output Peak Signal-to-Noise Ratio (PSNR) or other health metric. PURE is evaluated using an H.263 video encoder and shown to maintain signal processing throughput despite hardware faults. Its performance is compared to two alternative reconfiguration algorithms which prioritize the optimization of the number of reconfiguration occurrences and the fault detection latency, respectively. For a typical benchmark video sequence, PURE is shown to maintain a PSNR baseline near 32dB. Compared to the alternatives, PURE maintains a PSNR within a difference of 4.02dB to 6.67dB from the fault-free baseline by escalating healthy resources to higher-priority signal processing functions. The diagnosability, reconfiguration latency, and resource overhead of each approach is analyzed. The results indicate the benefits of priority-aware resiliency over conventional redundancy in terms of fault-recovery, power consumption, and resource-area requirements.

Exploring the epigenetic architecture of cognitive resilience in aging: A DNA methylation and a genetic scan converge on several loci associated with resilience

Exploring the epigenetic architecture of cognitive resilience in aging: A DNA methylation and a genetic scan converge on several loci associated with resilience

Resiliency in offshore wind farm communication networks

Wind energy is getting a considerable attention worldwide from the fraternity of the power system engineers as clean and green energy that can help reduce the carbon content and limit dependence on conventional fossil fuels. This has lead to the development of offshore wind farms in last few years. Real time monitoring and control of offshore wind farm require high speed, reliable, fault resilient, and cost effective communication infrastructure. The availability and reliability of wind energy mainly depend on resilient communication network. This can be achieved through a combination of redundancy and Quality of Service (QoS). In this paper, we have proposed fault resilient architecture of the medium scale offshore wind farm and simulated different fault scenarios based on IEC 61400-25 standard in OPNET. The wind farm communication is based on Transmission Control Protocol and Internet Protocol. The performance has been analysed with respect to QoS in terms of latency, traffic drop, and traffic congestion.

The Resilience Architecture Framework: Four organizational archetypes

This paper extends prior research in organizational resilience, which has failed to recognize that resilience can be a desirable or undesirable system characteristic depending on the system state. We introduce an organizational typology, the Resilience Architecture Framework (RAF), which forms a platform for the integration of divergent research streams – organizational rigidity, dynamic capabilities and organizational ambidexterity – into the study of organizational resilience. We conclude with framework implications and directions for future research.

Genetic architecture of resilience of executive functioning

The genetic basis of resilience, defined as better cognitive functioning than predicted based on neuroimaging or neuropathology, is not well understood. Our objective was to identify genetic variation associated with executive functioning resilience. We computed residuals from regression models of executive functioning, adjusting for age, sex, education, Hachinski score, and MRI findings (lacunes, cortical thickness, volumes of white matter hyperintensities and hippocampus). We estimated heritability and analyzed these residuals in models for each SNP. We further evaluated our most promising SNP result by evaluating cis-associations with brain levels of nearby (±100 kb) genes from a companion data set, and comparing expression levels in cortex and cerebellum from decedents with AD with those from other non-AD diseases. Complete data were available for 750 ADNI participants of European descent. Executive functioning resilience was highly heritable (H² = 0.76; S.E. = 0.44). rs3748348 on chromosome 14 in the region of RNASE13 was associated with executive functioning resilience (p-value = 4.31 × 10⁻⁷). rs3748348 is in strong linkage disequilibrium (D' of 1.00 and 0.96) with SNPs that map to TPPP2, a member of the α-synuclein family of proteins. We identified nominally significant associations between rs3748348 and expression levels of three genes (FLJ10357, RNASE2, and NDRG2). The strongest association was for FLJ10357 in cortex, which also had the most significant difference in expression between AD and non-AD brains, with greater expression in cortex of decedents with AD (p-value = 7 × 10⁻⁷). Further research is warranted to determine whether this signal can be replicated and whether other loci may be associated with cognitive resilience.

A Conceptual Framework for Research into Co-Operative Enterprise

This paper outlines a conceptual framework for approaching research into the co-operative enterprise business model and its sustainability. The model examines the co-op from three perspectives, that of the member, that of the co-op as a business entity, and the wider systems level. Key units of analysis for each level are outlined. Also considered within the model are three primary objectives for the co-op: the need to build identity; the need to build social capital and the need to build sustainability. The application of resilience architecture to help understand the dynamic behavior of the co-operative enterprise over time is also discussed.

Intelligent techniques and architectures for autonomic clouds: introduction to the itaac special issue

Autonomic Computing introduces autonomy in software systems by making them capable of self- management and self-healing. Autonomic Clouds have emerged as a result of the application of autonomic techniques to cloud computing, resulting in robust, fault tolerant and resilient cloud architectures. The international workshop on Intelligent Techniques and Architectures for Autonomic Clouds (ITAAC 2011) was held in association with the 4th IEEE/ACM International Conference on Utility and Cloud Computing (UCC 2011)in Melbourne Australia to bring together researchers and practitioners across Cloud Computing, Intelligent Systems, and Autonomic Computing to discuss issues that drive the concepts, architectures and applications of autonomic clouds. This article provides background to the workshop and presents a brief summary of the papers that were accepted.

Resilient Architectures via Collaborative Design: Maximizing Commodity Processor Performance in the Presence of Variations

Unintended variations in circuit lithography and undesirable fluctuations in circuit operating parameters such as supply voltage and temperature are threatening the continuation of technology scaling that microprocessor evolution relies on. Although circuit-level solutions for some variation problems may be possible, they are prohibitively expensive and impractical for commodity processors, on which not only the consumer market but also an increasing segment of the business market now depends. Solutions at the microarchitecture level and even the software level, on the other hand, overcome some of these circuit-level challenges without significantly raising costs or lowering performance. Using examples drawn from our Alarms Project and related work, we illustrate how collaborative design that encompasses circuits, architecture, and chip-resident software leads to a cost-effective solution for inductive voltage noise, sometimes called the <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dI</i> / <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">dt</i> problem. The strategy that we use for assuring correctness while preserving performance can be extended to other variation problems.

Power Gating Aware Task Scheduling in MPSoC

Shrinking the feature size allows more and better functions on a single chip. However, it makes multiprocessor system-on-chip (MPSoC) more susceptible to various reliability threats. Power supply noise is a major reliability problem faced by low power MPSoCs using power gating techniques. Powering on and off a processing unit in MPSoCs will induce large power/ground (P/G) noise and can cause timing divergence and even functional errors in surrounding processing units. Previous work on resilient architectures mainly focused on power/thermal management and neglected the important side-effect: P/G noise induced by power gating. In this paper, for the first time, we formulate a task scheduling problem with the consideration of P/G noise based on our detailed P/G noise analysis platform for MPSoC. Two efficient algorithms are proposed to reduce noise protection penalty and improve MPSoC performance. Our experiments show that both simulated annealing and heuristic algorithms can achieve on average 25% performance improvement together with up to 80% noise protection penalty saving compared with the conservative stop-go method for short tasks (shorter than 20 K clock cycles). For longer tasks up to 200 K clock cycles, the performance improvement of our methods will become relatively low. However, we can still achieve at least 35.2% noise protection penalty saving. Furthermore, a lightweight online adjustment strategy accompanying the offline scheduling method is proposed to adapt to runtime variations and improve reliability.

Resilient Security Architecture: A Complementary Approach to Reducing Vulnerabilities

The software industry would benefit from more emphasis on avoiding security mistakes in the first place. That means security requirements analysis and architecting and designing security in, an approach that's currently rare but that provides substantial benefits. The most common approaches to the latent (generally called 0-day) vulnerability problem fall into one of two categories: Do nothing. Wait for vulnerabilities to be discovered after release, and then patch them. Test security in. Implement code with vulnerabilities, and invest in finding or removing as many vulnerabilities as practical before release or production.

Multi-level Network Resilience: Traffic Analysis, Anomaly Detection and Simulation

Traffic analysis and anomaly detection have been extensively used to characterize network utilization as well as to identify abnormal network traffic such as malicious attacks. However, so far, techniques for traffic analysis and anomaly detection have been carried out independently, relying on mechanisms and algorithms either in edge or in core networks alone. In this paper we propose the notion of multi-level network resilience, in order to provide a more robust traffic analysis and anomaly detection architecture, combining mechanisms and algorithms operating in a coordinated fashion both in the edge and in the core networks. This work is motivated by the potential complementarities between the research being developed at IIT Madras and Lancaster University. In this paper we describe the current work being developed at IIT Madras and Lancaster on traffic analysis and anomaly detection, and outline the principles of a multi-level resilience architecture.

Voltage Noise in Production Processors

Voltage variations are a major challenge in processor design. Here, researchers characterize the voltage noise characteristics of programs as they run to completion on a production Core 2 Duo processor. Furthermore, they characterize the implications of resilient architecture design for voltage variation in future systems.