CernVM-FS powered container hub

Containers became the de-facto standard to package and distribute modern applications and their dependencies. The HEP community demonstrates an increasing interest in such technology, with scientists encapsulating their analysis workflow and code inside a container image. The analysis is first validated on a small dataset and minimal hardware resources to then run at scale on the massive computing capacity provided by the grid. The typical approach for distributing containers consists of pulling their image from a remote registry and extracting it on the node where the container runtime (e.g., Docker, Singularity) runs. This approach, however, does not easily scale to large images and thousands of nodes. CVMFS has long been used for the efficient distribution of software directory trees at a global scale. In order to extend its optimized caching and network utilization to the distribution of containers, CVMFS recently implemented a dedicated container image ingestion service together with container runtime integrations. CVMFS ingestion is based on per-file deduplication, instead of the per-layer deduplication adopted by traditional container registries. On the client-side, CVMFS implements on-demand fetching of the chunks required for the execution of the container instead of the whole image.

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Client-Side Caching Strategies and On-Demand Broadcast Algorithms for Real-Time Information Dispatch Systems

IEEE Transactions on Broadcasting ◽

10.1109/tbc.2007.912850 ◽

2008 ◽

Vol 54 (1) ◽

pp. 24-35 ◽

Cited By ~ 22

Author(s):

Joseph Kee-Yin Ng ◽

Victor Chung-Sing Lee ◽

Chui Ying Hui

Keyword(s):

Real Time ◽

On Demand ◽

Client Side ◽

Real Time Information ◽

Time Information ◽

Caching Strategies

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A P2P Home-Box Overlay for Efficient Content Distribution

Emerging Innovations in Wireless Networks and Broadband Technologies - Advances in Wireless Technologies and Telecommunication ◽

10.4018/978-1-4666-9941-0.ch009 ◽

2016 ◽

pp. 199-220 ◽

Cited By ~ 1

Author(s):

Evangelos Markakis ◽

Daniel Negru ◽

Joachim Bruneau-Queyreix ◽

Evangelos Pallis ◽

George Mastorakis ◽

...

Keyword(s):

Overlay Networks ◽

Content Distribution ◽

Video On Demand ◽

Resource Usage ◽

Caching Strategy ◽

Content Caching ◽

On Demand ◽

Cost Efficient ◽

Client Side ◽

Distribution Cost

The overlay networks composed of residential gateways (i.e. home-box) leverage their storage and upload capacity to achieve scalable and cost-efficient content distribution. In this chapter, we present the architecture of the home-box overlay for video on demand services, with the network-aware request redirection and content caching strategy that optimizes the resource usage at both network and client side, for reducing the overall distribution cost. The proposed system is compared with existing solutions through comprehensive simulations. The results demonstrate the advantage of network-aware and popularity-based caching strategy, with reduced the overall cost of the VoD services.

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ON THE CATEGORIZATION OF HIGH ACTIVITY OBJECTS USING DIFFERENTIAL ATTRIBUTE PROFILES

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xlii-1-59-2018 ◽

2018 ◽

Vol XLII-1 ◽

pp. 59-64 ◽

Cited By ~ 1

Author(s):

M. Boldt ◽

A. Thiele ◽

K. Schulz ◽

S. Hinz

Keyword(s):

High Activity ◽

Land Use Land Cover ◽

Change Analysis ◽

On Demand ◽

Time Series Dataset ◽

Analysis Workflow ◽

Category Type ◽

Feature Based ◽

Change Event

Abstract. Change detection represents a broad field of research being on demand for different applications (e.g. disaster management and land use / land cover monitoring). Since the detection itself only delivers information about location and date of the change event, it is limited against approaches dealing with the category, type, or class of the change objects. In contrast to classification, categorization denotes a feature-based clustering of entities (here: change objects) without using any class catalogue information. Therefore, the extraction of suitable features has to be performed leading to a clear distinction of the resulting clusters.In previous work, a change analysis workflow has been accomplished, which comprises both the detection, the categorization, and the classification of so-called high activity change objects extracted from a TerraSAR-X time series dataset. With focus on the features used in this study, the morphological differential attribute profiles (DAPs) turned out to be very promising. It was shown, that the DAP were essential for the construction of the principal components.In this paper, this circumstance is considered. Moreover, a change categorization based only on different and complementary DAP features is performed. An assessment concerning the best suitable features is given.

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The active pleasures of expression and communication

Comunicar ◽

10.3916/c30-2008-01-003 ◽

2008 ◽

Vol 15 (30) ◽

pp. 21-26

Author(s):

James James Lull

Keyword(s):

Communication Technology ◽

Social Power ◽

Global Scale ◽

Symbolic Power ◽

Recent Book ◽

Human Communication ◽

On Demand ◽

Communication Processes ◽

Contemporary Media ◽

Medios De Comunicacion

Based on Lull’s recent book «Culture-on-Demand: Communication in a Crisis World» (2007) and on the author’s view of audiences as active participants in all forms of human communication, this article argues for the place of human expression and symbolic power in contemporary media and cultural studies. It also discusses how modern communication technology reinforces and extends the expressive potential of ordinary citizens in the normative contexts of everyday life. This contribution introduces the concept of cultural open sourcing as fundamental to the increasing democratization of communication processes and distribution of social power ona global scale.Adaptado a partir del más reciente libro de su autor, «Culture-on-demand: communication in a crisis world», y continuando con la visión que el autor tiene de la participación activa de los espectadores en todas las formas de comunicación humana, este artículo defiende el lugar de la expresión humana y del poder del símbolo en los medios de comunicación contemporáneos y en el mundo de la cultura. Discute cómo la moderna tecnología de la comunicación refuerza y extiende el potencial expresivo de los ciudadanos de a pie en los contextos normativos de la vida cotidiana e introduce el concepto de cultural «open sourcing», concepto fundamental para incrementar la democratización de los procesos de la comunicación y la distribución del poder social a escala global.

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Distribution equality as an optimal epidemic mitigation strategy

10.1101/2020.09.15.20194506 ◽

2020 ◽

Author(s):

Adar Hacohen ◽

Reuven Cohen ◽

Sol Efroni ◽

Ido Bachelet ◽

Baruch Barzel

Keyword(s):

Supply And Demand ◽

Global Scale ◽

Mitigation Strategy ◽

Optimal Conditions ◽

Supply Rate ◽

Dissemination Strategy ◽

Viral Spread ◽

Global Pandemic ◽

Rapid Dissemination ◽

Efficient Distribution

Upon the development of a drug or vaccine, a successful response to a global pandemic, such as COVID-19, requires the capacity for efficient distribution at a global scale. Considering constraints on production and shipping, most existing strategies seek to maximize the outflow of therapeutics, hence optimizing for rapid dissemination. Surprisingly, we find that this intuitive approach is counterproductive. The reason is that focusing strictly on the quantity of disseminated therapeutics, such strategies disregard their specific spreading patterns, most crucially, they overlook the interplay of these spreading patterns with those of the pathogens. This results in a discrepancy between supply and demand, that prohibits efficient mitigation even under optimal conditions of superfluous drug/vaccine flow. Therefore, here, we design a dissemination strategy that naturally follows the predicted spreading patterns of the epidemic, optimizing not just for supply volume, but also for its congruency with the anticipated demand. Specifically, we show that epidemics spread relatively uniformly across all destinations, and hence we introduce an equality constraint into our dissemination that prioritizes supply homogeneity. This strategy may, at times, slow down the supply rate in certain locations, however, thanks to its egalitarian nature, which mimics the flow of the viral spread, it provides a dramatic leap in overall mitigation efficiency, saving more lives with orders of magnitude less resources.

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Demystifying COVID-19 Digital Contact Tracing: A Survey on Frameworks and Mobile Apps

Wireless Communications and Mobile Computing ◽

10.1155/2020/8851429 ◽

2020 ◽

Vol 2020 ◽

pp. 1-29

Author(s):

Tania Martin ◽

Georgios Karopoulos ◽

José L. Hernández-Ramos ◽

Georgios Kambourakis ◽

Igor Nai Fovino

Keyword(s):

Mobile Apps ◽

Global Scale ◽

Contact Tracing ◽

Network Technology ◽

Full Spectrum ◽

Ongoing Effort ◽

Modus Vivendi ◽

Model Section ◽

Client Side ◽

Adversary Model

The coronavirus pandemic is a new reality, and it severely affects the modus vivendi of the international community. In this context, governments are rushing to devise or embrace novel surveillance mechanisms and monitoring systems to fight the outbreak. The development of digital tracing apps, which among others are aimed at automatising and globalising the prompt alerting of individuals at risk in a privacy-preserving manner, is a prominent example of this ongoing effort. Very promptly, a number of digital contact tracing architectures have been sprouted, followed by relevant app implementations adopted by governments worldwide. Bluetooth, specifically its Low Energy (BLE) power-conserving variant, has emerged as the most promising short-range wireless network technology to implement the contact tracing service. This work offers the first to our knowledge full-fledged review of the most concrete contact tracing architectures proposed so far in a global scale. This endeavour does not only embrace the diverse types of architectures and systems, namely, centralised, decentralised, or hybrid, but also equally addresses the client side, i.e., the apps that have been already deployed in Europe by each country. There is also a full-spectrum adversary model section, which does not only amalgamate the previous work in the topic but also brings new insights and angles to contemplate upon.

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Localized Multistreams for P2P Streaming

International Journal of Digital Multimedia Broadcasting ◽

10.1155/2010/843574 ◽

2010 ◽

Vol 2010 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Majed Alhaisoni ◽

Mohammed Ghanbari ◽

Antonio Liotta

Keyword(s):

Cellular Networks ◽

Video On Demand ◽

Streaming Video ◽

Dynamic Nature ◽

P2p Streaming ◽

On Demand ◽

User Terminal ◽

Network Utilization ◽

Simulation Based ◽

A New Technique

Streaming video over the Internet, including cellular networks, has now become a commonplace. Network operators typically use multicasting or variants of multiple unicasting to deliver streams to the user terminal in a controlled fashion. P2P streaming is an emerging alternative, which is theoretically more scalable but suffers from other issues arising from the dynamic nature of the system. Users' terminals become streaming nodes but they are not constantly connected. Another issue is that they are based on logical overlays, which are not optimized for the physical underlay infrastructure. An important proposition is to find effective ways to increase the resilience of the overlay whilst at the same time not conflicting with the network. In this article we look at the combination of two techniques, redundant streaming and locality awareness, in the context of both live and video-on-demand streaming. We introduce a new technique and assess it via a comparative, simulation-based study. We find that redundancy affects network utilization only marginally if traffic is kept at the edges via localization techniques.

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