http://wpage.unina.it/valerio.persico/pubs/CloudIoT_FGCS.pdf

Integration of Cloud computing and Internet of Things

Video on-demand streaming from Internet-based servers is becoming one of the most important services offered by wireless networks today. In order to improve the area spectral efficiency of video transmission in cellular systems, small cells heterogeneous architectures (e.g., femtocells, WiFi off-loading) are being proposed, such that video traffic to nomadic users can be handled by short-range links to the nearest small cell access points (referred to as “helpers”). As the helper deployment density increases, the backhaul capacity becomes the system bottleneck. In order to alleviate such bottleneck we propose a system where helpers with low-rate backhaul but high storage capacity cache popular video files. Files not available from helpers are transmitted by the cellular base station. We analyze the optimum way of assigning files to the helpers, in order to minimize the expected downloading time for files. We distinguish between the uncoded case (where only complete files are stored) and the coded case, where segments of Fountain-encoded versions of the video files are stored at helpers. We show that the uncoded optimum file assignment is NP-hard, and develop a greedy strategy that is provably within a factor 2 of the optimum. Further, for a special case we provide an efficient algorithm achieving a provably better approximation ratio of 1-(1-1/d )d, where d is the maximum number of helpers a user can be connected to. We also show that the coded optimum cache assignment problem is convex that can be further reduced to a linear program. We present numerical results comparing the proposed schemes.

FemtoCaching: Wireless Content Delivery Through Distributed Caching Helpers

The present embodiments provide methods, systems and apparatuses for use in managing content on at least a local network. Some embodiments provide a method for use in managing content that detects there is a change to content on a local network, determines whether the change is additional content on a first client device, determines whether the additional content can be identified, determines whether there is a predictive distribution scheme when the additional content is identified, distributes the additional content over the local network according the predictive distribution scheme when a predictive distribution scheme applies to the additional content, determines whether a new predictive distribution scheme can be defined when a predictive distribution scheme does not apply to the additional content, and saving the new predictive distribution scheme when a new predictive scheme can be defined.

Methods and systems for use in network management of content

Certain data-communication protocols hog the spotlight, but all of them have a lot in common. Computer Networking: A Top-Down Approach Featuring the Internet explains the engineering problems that are inherent in communicating digital information from point to point. The top-down approach mentioned in the subtitle means that the book starts at the top of the protocol stack--at the application layer--and works its way down through the other layers, until it reaches bare wire. The authors, for the most part, shun the well-known seven-layer Open Systems Interconnection (OSI) protocol stack in favor of their own five-layer (application, transport, network, link, and physical) model. It's an effective approach that helps clear away some of the hand waving traditionally associated with the more obtuse layers in the OSI model. The approach is definitely theoretical--don't look here for instructions on configuring Windows 2000 or a Cisco router--but it's relevant to reality, and should help anyone who needs to understand networking as a programmer, system architect, or even administration guru.The treatment of the network layer, at which routing takes place, is typical of the overall style. In discussing routing, authors James Kurose and Keith Ross explain (by way of lots of clear, definition-packed text) what routing protocols need to do: find the best route to a destination. Then they present the mathematics that determine the best path, show some code that implements those algorithms, and illustrate the logic by using excellent conceptual diagrams. Real-life implementations of the algorithms--including Internet Protocol (both IPv4 and IPv6) and several popular IP routing protocols--help you to make the transition from pure theory to networking technologies. --David WallTopics covered: The theory behind data networks, with thorough discussion of the problems that are posed at each level (the application layer gets plenty of attention). For each layer, there's academic coverage of networking problems and solutions, followed by discussion of real technologies. Special sections deal with network security and transmission of digital multimedia.

Computer Networking: A Top-Down Approach

We suggest a novel approach to handle the ongoing explosive increase in the demand for video content in wireless/mobile devices. We envision femtocell-like base stations, which we call helpers, with weak backhaul links but large storage capacity. These helpers form a wireless distributed caching network that assists the macro base station by handling requests of popular files that have been cached. Due to the short distances between helpers and requesting devices, the transmission of cached files can be done very efficiently.

FemtoCaching: Wireless video content delivery through distributed caching helpers

https://www.cse.fau.edu/~xqzhu/courses/Resources/characterize.of.youtube.pdf

Characteristics of YouTube network traffic at a campus network - Measurements, models, and implications

Given the highly empirical nature of research in cloud computing, networked systems, and related fields, testbeds play an important role in the research ecosystem. In this paper, we cover one such facility, CloudLab, which supports systems research by providing raw access to programmable hardware, enabling research at large scales, and creating a shared platform for repeatable research.

We present our experiences designing CloudLab and operating it for four years, serving nearly 4,000 users who have run over 79,000 experiments on 2,250 servers, switches, and other pieces of datacenter equipment. From this experience, we draw lessons organized around two themes. The first set comes from analysis of data regarding the use of CloudLab: how users interact with it, what they use it for, and the implications for facility design and operation. Our second set of lessons comes from looking at the ways that algorithms used "under the hood," such as resource allocation, have important-- and sometimes unexpected--effects on user experience and behavior. These lessons can be of value to the designers and operators of IaaS facilities in general, systems testbeds in particular, and users who have a stake in understanding how these systems are built.

/pdf/the-design-and-operation-of-cloudlab-52c7h9x9c7.pdf

The design and operation of cloudlab

We consider the problem of allocating networked resources in dynamic environment, such as cloud computing platforms, where providers strategically price resources to maximize their utility. Resource allocation in these environments, where both providers and consumers are selfish agents, presents numerous challenges since the number of consumers and their resource demand is highly dynamic. While numerous auction-based approaches have been proposed in the literature, this paper explores an alternative approach where providers and consumers automatically negotiate resource leasing contracts. Since resource demand and supply can be dynamic and uncertain, we propose a distributed negotiation mechanism where agents negotiate over both a contract price and a decommitment penalty, which allows agents to decommit from contracts at a cost. We compare our approach experimentally, using representative scenarios and workloads, to both combinatorial auctions and the fixed-price model used by Amazon's Elastic Compute Cloud, and show that the negotiation model achieves a higher social welfare.

/pdf/automated-negotiation-with-decommitment-for-dynamic-resource-35t233i4x0.pdf

Automated negotiation with decommitment for dynamic resource allocation in cloud computing

Web services such as YouTube which allow the distribution of user-produced media have recently become very
popular YouTube-like services are different from existing traditional VoD services because the service provider
has only limited control over the creation of new content We analyze how the content distribution in YouTube
is realized and then conduct a measurement study of YouTube traffic in a large university campus network The
analysis of the traffic shows that: (1) No strong correlation is observed between global and local popularity; (2)
neither time scale nor user population has an impact on the local popularity distribution; (3) video clips of local
interest have a high local popularity Using our measurement data to drive trace-driven simulations, we also
demonstrate the implications of alternative distribution infrastructures on the performance of a YouTube-like
VoD service The results of these simulations show that client-based local caching, P2P-based distribution, and
proxy caching can reduce network traffic significantly and allow faster access to video clips

/pdf/watch-global-cache-local-youtube-network-traffic-at-a-campus-2f6sxa40v0.pdf

Watch Global, Cache Local: YouTube Network Traffic at a Campus Network - Measurements and Implications

Layer encoded video is an elegant way to allow adaptive transmissions in the face of varying network conditions as well as it supports heterogeneity in networks and clients. As a drawback quality degradation can occur, caused by variations in the amount of transmitted layers. Recent work on reducing these variations makes assumptions about the perceived quality of those videos. The main goal of this paper respectively its motivation is to investigate the validity of these assumptions by subjective assessment. However, the paper is also an attempt to investigate fundamental issues for the human perception of layer encoded video with time-varying quality characteristics. For this purpose, we built a test environment for the subjective assessment of layer encoded video and conducted an empirical experiment in which 66 test candidates took part. The results of this subjective assessment are presented and discussed. To a large degree we were able to validate existing (unproven) assumptions about quality degradation caused by variations in layer encoded videos, however there were also some interesting, at first sight counterintuitive findings from our experiment.

Michael Zink

Papers

Characteristics of YouTube network traffic at a campus network - Measurements, models, and implications

The design and operation of cloudlab

Automated negotiation with decommitment for dynamic resource allocation in cloud computing

Watch Global, Cache Local: YouTube Network Traffic at a Campus Network - Measurements and Implications

Subjective impression of variations in layer encoded videos