Now showing items 1-20 of 25

  • Asymptotic laws for content replication and delivery in wireless networks 

    Gitzenis, S.; Paschos, G. S.; Tassiulas, L. (2012)
    A key consideration in novel communication paradigms in multihop wireless networks regards the scalability of the network. We investigate the case of nodes making random requests on content stored in multiple replicas over ...
  • Asymptotic Laws for Joint Content Replication and Delivery in Wireless Networks 

    Gitzenis, S.; Paschos, G. S.; Tassiulas, L. (2013)
    We investigate the scalability of multihop wireless communications, a major concern in networking, for the case that users access content replicated across the nodes. In contrast to the standard paradigm of randomly selected ...
  • Caching in content-based publish/subscribe systems 

    Sourlas, V.; Paschos, G. S.; Flegkas, P.; Tassiulas, L. (2009)
    In a publish/subscribe network, message delivery is guaranteed for all active subscribers at publish time. However, in a dynamic scenario where users join and leave the network, a user may be interested in content published ...
  • A demonstration of multirate multicast over an 802.11 mesh network 

    Paschos, G. S.; Li, C. P.; Modiano, E.; Choumas, K.; Korakis, T. (2014)
    This demo presents a novel multirate multicast scheme for video delivery to wireless users. We demonstrate an adaptive scheme that combines differential backlog scheduling and intelligent packet dropping, both based on ...
  • Distribute, store and retrieve management policies in wireless ad-hoc networks using the content delivery publish/subscribe paradigm 

    Sourlas, V.; Flegkas, P.; Paschos, G. S.; Tassiulas, L. (2009)
    Policy management is a management paradigm that has been extensively studied for the case of fixed networks but limited work can be found for migrating it to mobile environments. It enables dynamic adaptation of the network ...
  • Dynamic CPU scheduling for QoS provisioning 

    Katsalis, K.; Paschos, G. S.; Tassiulas, L.; Viniotis, Y. (2013)
    Distributed, large-scale, enterprise applications are commonly supported in multi-tier data-center environments. In this paper, we study a scheduling problem for sharing CPU time in a cluster of servers among a number of ...
  • Dynamic overload balancing in server farms 

    Li, C. P.; Paschos, G. S.; Tassiulas, L.; Modiano, E. (2014)
    We consider the problem of optimal load balancing in a server farm under overload conditions. A convex penalty minimization problem is studied to optimize queue overflow rates at the servers. We introduce a new class of ...
  • Dynamic Wireless Network Coding With Overhearing and Variable Channel Rates 

    Fragiadakis, C.; Paschos, G. S.; Georgiadis, L.; Tassiulas, L. (2015)
    We study a one-hop broadcast channel with two receivers. The receivers have side information obtained by overhearing wireless channels. The relay takes control decisions by coding transmissions based on its knowledge of ...
  • The effect of caching in sustainability of large wireless networks 

    Paschos, G. S.; Gitzenis, S.; Tassiulas, L. (2012)
    We study the scalability of multihop wireless communications, a major concern in networking, for the case that users access content cached across the nodes. In contrast to the standard paradigm of randomly selected ...
  • Energy OPtimal ALgorithms for mobile Internet: Stochastic modeling, performance analysis and optimal control 

    Paschos, G. S.; Mannersalo, P.; Stanczak, S.; Altman, E.; Tassiulas, L. (2011)
    EnergyOPAL research focused on algorithms which can enable an energy friendly future mobile Internet. Turning off the electronics of a wireless device is understood to be crucial for saving energy over idle periods. On the ...
  • Enhancing wireless networks with caching: Asymptotic laws, sustainability & trade-offs 

    Gitzenis, S.; Paschos, G. S.; Tassiulas, L. (2014)
    We investigate on the sustainability of multihop wireless communications in the context of Information-Centric Networks, when content is replicated in caches over the network. The problem is cast in a flat wireless network ...
  • Medium access games: The impact of energy constraints 

    Gkatzikis, L.; Paschos, G. S.; Koutsopoulos, I. (2011)
    We consider random medium access schemes for devices that support sleep modes, i.e. turning off electronic compartments for energy saving. Due to hardware limitations, sleep mode transitions cannot occur at the medium ...
  • Minimal Evacuation Times and Stability 

    Georgiadis, L.; Paschos, G. S.; Libman, L.; Tassiulas, L. (2015)
    We consider a system where packets (jobs) arrive for processing using one of the policies in a given class. We study the connection between the minimal evacuation time and the stability region of the system and show that ...
  • Mobility support through caching in content-based publish/subscribe networks 

    Sourlas, V.; Paschos, G. S.; Flegkas, P.; Tassiulas, L. (2010)
    In a publish/subscribe (pub/sub) network, message delivery is guaranteed for all connected subscribers at publish time. However, in a dynamic mobile scenario where users join and leave the network, it is important that ...
  • Modeling the dynamics of caching in content-based publish/subscribe systems 

    Sourlas, V.; Paschos, G. S.; Mannersalo, P.; Flegkas, P.; Tassiulas, L. (2011)
    This paper considers cache dimensioning in the context of publish/subscribe (pub/sub) systems. We assume that each broker is equipped with a limited capacity cache and it decides upon a policy for caching and prioritizing ...
  • A modular framework for implementing joint wireless network coding and scheduling algorithms 

    Broustis, I.; Paschos, G. S.; Syrivelis, D.; Georgiadis, L.; Tassiulas, L. (2013)
    Intersession network coding (NC) can provide significant performance benefits via mixing packets at wireless routers; these benefits are especially pronounced when NC is applied in conjunction with intelligent scheduling. ...
  • Multirate multicast: Optimal algorithms and implementation 

    Paschos, G. S.; Li, C. P.; Modiano, E.; Choumas, K.; Korakis, T. (2014)
    Multirate multicast improves user quality but complicates network optimization. This paper introduces a novel control scheme to dynamically optimize multirate multicast. We present MMT, an adaptive policy which combines ...
  • On the Wireless Network Coding with overhearing and index coding 

    Fragiadakis, C.; Paschos, G. S.; Tassiulas, L. (2013)
    We study the problem of Wireless Network Coding with imperfect overhearing, a joint coding/scheduling problem that arises naturally in multihop wireless networks. We map this problem to specific instances of index coding. ...
  • Optimal Control of Sleep Periods for Wireless Terminals 

    Azad, A. P.; Alouf, S.; Altman, E.; Borkar, V.; Paschos, G. S. (2011)
    We consider a mobile connected to a base station, and study how to optimally schedule shutting off its transceiver. First, we study the model from optimal control perspective. We consider off-times (periods of inactivity) ...
  • Scheduling with pairwise XORing of packets under statistical overhearing information and feedback 

    Paschos, G. S.; Georgiadis, L.; Tassiulas, L. (2012)
    We study the problem of scheduling packets from several flows traversing a given node which can mix packets belonging to different flows. Practical wireless network coding solutions depend on knowledge of overhearing events ...