• When & Where: Seminars are generally (please, check the timeline and location before coming!) held on:
    • Wednesday afternoon at LINCS (14h-15h, Salle de Conseil) and
    • Thursday afternoon at Barrault (14h-15h, Amphi Saphir).
  • Contact us: if you wish to give a talk on networking, math, software or embedded-system topics, do not hesitate to contact us

[Next talks] [All talks]

07/09/2016 (@LINCS, Seminar Room)Andread Araldo (Telecom ParisTech and Paris XI/LRI)Dynamic Cache Partitioning for Encrypted Content Delivery
07/09/2016 (@LINCS, Seminar Room)Mathis Obadia (Telecom ParisTech and Thales)Network Function Virtualization; Techno-Economics

Date:07/09/2016, 14h00
Room:LINCS, Seminar Room
Speaker:Andread Araldo (Telecom ParisTech and Paris XI/LRI)
Talk:Dynamic Cache Partitioning for Encrypted Content Delivery
Abstract:In-network caching is an appealing solution to cope with the increasing bandwidth demand of video, audio and data transfer over the Internet. Nonetheless, an increasing share of content delivery services adopt encryption through HTTPS, which is not compatible with traditional ISP-managed approaches like transparent and proxy caching. This raises the need for solutions involving both Internet Service Providers (ISP) and Content Providers (CP): by design, the solution should preserve business-critical CP information (e.g., content popularity, user preferences) on the one hand, while allowing for a deeper integration of caches in the ISP architecture (e.g., in 5G femto-cells) on the other hand. In this paper we address this issue by considering a content-oblivious ISP-operated cache. The ISP allocates the cache storage to various content providers so as to maximize the bandwidth savings provided by the cache: the main novelty lies in the fact that, to protect business-critical information, ISPs only need to measure the aggregated miss rates of the individual CPs. We propose a cache allocation algorithm based on a perturbed stochastic subgradient method, and prove that the algorithm converges to the allocation that maximizes the overall cache hit rate. We use extensive simulations to validate the algorithm and to assess its convergence rate under stationary and non-stationary content popularities. Our results (i) testify the feasibility of content-oblivious caches and (ii) show that the proposed algorithm can achieve within 15% from the global optimum in our evaluation. Joint work with Gyorgy Dan and Dario Rossi, to appear at ITC28 https://itc28.org/
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Date:07/09/2016, 14h30
Room:LINCS, Seminar Room
Speaker:Mathis Obadia (Telecom ParisTech and Thales)
Talk:Network Function Virtualization; Techno-Economics
Abstract:Network Function Virtualization (NFV) is an emerging approach that has received attention from both academia and industry as a way to improve flexibility, efficiency, and manageability of networks. NFV enables new ways to operate networks and to provide composite network services, opening the path toward new business models. As in cloud computing with the Infrastructure as a Service model, clients will be offered the capability to provision and instantiate Virtual Network Functions (VNF) on the NFV infrastructure of the network operators. In this paper, we consider the case where leftover VNF capacities are offered for bid. This approach is particularly interesting for clients to punctually provision resources to absorb peak or unpredictable demands and for operators to increase their revenues. We propose a game theoretic approach and make use of Multi-Unit Combinatorial Auctions to select the winning clients and the price they pay. Such a formulation allows clients to express their VNF requests according to their specific objectives. We solve this problem with a greedy heuristic and prove that this approximation of economic efficiency is the closest attainable in polynomial time and provides a payment system that motivates bidders to submit their true valuations. Simulation results show that the proposed heuristic achieves a market valuation close to the optimal (less than 10 % deviation) and guarantees that an important part of this valuation is paid as revenue to the operator. Joint work with Jean-Louis Rougier, Luigi Iannone, Mathieu Bouet and Vania Conan, to appear at ITC28 https://itc28.org/
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