In this paper we study the statistics of the realized throughput of elastic document transfers, accounting for the way network bandwidth is shared dynamically between the randomly varying number of concurrent flows. We first discuss the way TCP realizes statistical bandwidth sharing, illustrating essential properties by means of packet level simulations.… (More)
— Though initially designed for data transport, there is increasing interest in using the 802.11 WLAN protocol for voice and other real time services. This paper presents a performance model for voice over WLAN under distributed control. The model is based on classical decoupling arguments and allows an analytical evaluation of network capacity in terms of… (More)
So-called elastic flows, corresponding to document transfers of various types, constitute the bulk of Internet traffic. This paper presents models of a single bottleneck link handling elastic traffic, accounting for random flow arrivals. The transport protocol and packet scheduling are taken into account approximately by assuming perfectly realized… (More)
— We present a rate control algorithm adapted to MPEG video coders ensuring that output conforms to the parameters of a leaky-bucket network access controller. The algorithm avoids unpredictable rate variations without the rigidity and systematic coding delay of constant bit-rate (CBR) coders, and makes possible resource provision for guaranteed quality of… (More)
It is proposed to apply an integrated admission control scheme to both streaming flows and elastic flows. It is assumed that streaming flow packets are served with priority in network queues so that admission control ensures minimal delay for audio and video applications while preserving the throughput of document transfers. An implicit measurement-based… (More)
While providers generally aim to avoid congestion by adequate provisioning, overload can clearly occur on certain network links. In this paper we propose some simple preliminary models for an overloaded link accounting for user impatience and reattempt behavior.
A bidding process can be organized so that offers are submitted simultaneously or sequentially. In the latter case, potential buyers can condition their behavior on previous entrants' decisions. The relative performance of these mechanisms is investigated when entry is costly and selective, meaning that potential buyers with higher values are more likely to… (More)
We examined the hypothesis that different processes and representations are associated with the learning of a movement sequence through motor-execution and action-observation. Following a pre-test in which participants attempted to achieve an absolute, and relative, time goal in a sequential goal-directed aiming movement, participants received either… (More)