2,092 research outputs found
Algorithms for advance bandwidth reservation in media production networks
Media production generally requires many geographically distributed actors (e.g., production houses, broadcasters, advertisers) to exchange huge amounts of raw video and audio data. Traditional distribution techniques, such as dedicated point-to-point optical links, are highly inefficient in terms of installation time and cost. To improve efficiency, shared media production networks that connect all involved actors over a large geographical area, are currently being deployed. The traffic in such networks is often predictable, as the timing and bandwidth requirements of data transfers are generally known hours or even days in advance. As such, the use of advance bandwidth reservation (AR) can greatly increase resource utilization and cost efficiency. In this paper, we propose an Integer Linear Programming formulation of the bandwidth scheduling problem, which takes into account the specific characteristics of media production networks, is presented. Two novel optimization algorithms based on this model are thoroughly evaluated and compared by means of in-depth simulation results
Recommended from our members
A directionally based bandwidth reservation scheme for call admission control
This paper proposes a new advanced Call Admission Control(CAC) strategy involving for the first time, a bandwidth reservation scheme that is influenced by the direction attribute of a mobile terminal (MT). Aside from the Quality-of-Service (QoS) parameters, the direction attribute plays a key role in efficiently reserving resources for MTs supporting multimedia communications for different QoS classes. The framework for a direction-based CAC system is entirely distributed and may be viewed as a message passing system, where MTs inform their neighbouring base stations (BS) not only of their QoS requirements, but also of their mobility parameters. The base stations then predict future demand and reserve resources accordingly, only admitting those terminals that can be adequately supported. The bandwidth reservation scheme proposed in this paper, integrates the direction attribute into the conventional Guard Channel (GC) scheme. Simulation results prove that this new scheme offers significant improvements in both Call Blocking Probability (CBP) and bandwidth utilization, under a variety of differing traffic conditions
Bandwidth reservation in mobile adhoc networks
International audienceThe bandwidth reservation is one of most adopted solutions to meet QoS requirements in 802.11 ad hoc networks. The efficiency of these solutions depends on the accuracy of their estimations of available bandwidth; otherwise, their application can be catastrophic on networks. Therefore, accurate bandwidth estimation is fundamental, where each networks characteristic must be taken into consideration, including mobility and medium sharing. Current solutions do not take into account all networks characteristics, resulting to wrong bandwidth estimations and QoS violations. In this paper, we present a new approach for bandwidth reservation-Accurate Bandwidth Reservation (ABR)-which embeds an improved method of available bandwidth measurement, where all criteria of such networks are considered. Evaluation of ABR is performed by simulations and comparisons with some existing approaches
BRuIT : Bandwidth Reservation under Interferences Influence
This paper deals with the bandwidth reservation problem in ad hoc networks and with the influence that interferences between signals have on this problem. We show that interferences could decrease the applications rates. This can be a real problem for applications that need guarantees. We propose a distributed protocol (called BRuIT) for bandwidth reservation in ad hoc networks that takes into account the existence of interferences from far transmissions. The protocol is analyzed through simulations carried out under NS: we evaluate the signaling overhead required for maintaining the knowledge of existing interferences ; we show that this knowledge reduces delays in case of congestion ; we measure the time for rebuilding broken routes ; and finally we show that this protocol maintains the rate of accepted applications.Cet article traite du problème de réservation de bande passante dans les réseaux ad-hoc et de l’influence des interférences hertziennes sur ce problème. Nous montrons que le phénomène d’interférences peut être à l’origine de pertes de bande passante qui peuvent être problématique pour les applications nécessitant des garanties. nous proposons un protocole distribué de réservation de bande passante pour réseaux ad-hoc appelé BRuIT. Ce protocole prend en compte l’existence d’interférences entre transmissions lointaines. Les performances de BRuIT sont analysées au moyen de simulations sous NS
Bandwidth Reservation in Multihop Wireless Networks: Complexity and Mechanisms
We show that link interferences in wireless networks make multihop bandwidth reservation in such an environment an NP-complete problem. This is in sharp contrast to bandwidth reservation in wireline networks where efficient polynomial algorithms exist. We also consider the problem of slot allocation according to bandwidth requirements in a wireless slotted environment. In the context of Mobile Ad Hoc Networks, we propose simple heuristics applicable to the OLSR routing protocol in order to find routes that satisfies requirements without impairing the performance of other connections
Effective Loss of Multiplexed ATM Cell Streams
Cell loss is an inherent problem of ATM networks. The magnitude of the service degeneration caused by cell loss depends on the application and loss distribution. This paper introduces a new performance criterion, called effective loss, which can quantitatively measure this degradation. Effective loss is particularly suitable for block-oriented transmissions, such as file transfer applications, but can also be applied to a broad range of other applications. In this paper the effective loss measure is applied to the study of the effectiveness of bandwidth reservation mechanisms in an ATM multiplexer. Numerical results demonstrate circumstances under which bandwidth reservation improves performance as well as circumstances in which it degrades performance
- …