Anton Kiryanov

Modeling of real-time multimedia streaming with deterministic access

To provide Quality of service (QoS) in wireless networks, deterministic channel access is often used. The key idea of the method is to provide a prerogative to a station to access the channel during allocated time intervals called reservations. The existed protocol standards define how to set up a reservation but do not describe how many reservations should be allocated to meet QoS requirements. This challenging issue is complicated in case of a real-time multimedia stream of variable bitrate. To address this issue, in the paper, we propose an algorithm of dynamic resource allocation for the stream in the presence of noise.

Analytical study of neighborhood discovery and link management in OLSR

In mobile ad-hoc networks (MANETs), neighborhood discovery and link management (NDLM) mechanism is used by each node to determine the set of its neighbors, or in other words, to establish one-hop links. Values of this mechanism parameters dramatically affect network performance, especially when real-time traffic is transmitted with proactive routing protocols, which imposes constraints on link quality, i.e. reliability, stability and decision-making latency. The efficiency of NDLM mechanisms is usually evaluated by simulation. The core contribution of this paper is an analytical study of NDLM mechanism defined in OLSR protocol specification. With the developed analytical model of the mechanism, we find the set of parameter values which allow to meet the constraints on link quality indices. By simulation, we show that the usage of these values improves the performance of the network loaded with voice traffic.

A method to estimate efficiency of the connection control mechanisms in wireless self-organizing networks

An original method to estimate efficiency of the algorithms for opening and closing links in the wireless self-organizing networks (mesh networks) was proposed. It can be used to develop a mathematical model of the algorithm standardized in the mesh network specification IEEE 802.11s. The proposed method was shown to be sufficiently general and applicable to developing the models of other link management algorithms.

Analysis of logical topology construction mechanisms in MANET

Link management mechanisms (LMMs) are responsible for the formation of the logical topology of networks by opening and closing links between stations and are an integral part of most of proactive routing protocols. In this work, a class of LMMs is analyzed in which the decision on opening and closing links is made on the basis of a sequence of received/lost special control messages. In particular, the considered class includes LMMs employed in the well-known OLSR and TBRPF routing protocols. An analytical model of this class of LMM, enabling one to analyze the efficiency of different LMMs and recommend the choice of their parameters, is developed.

P-persistent queue management to overcome channel failures in IEEE 802.11 networks for real-time multimedia streaming

In the paper, we consider real-time video streaming over an IEEE 802.11 network in the presence of short-term channel failures. The failures can dramatically decrease the received video quality at all network stations, even if the channel fails for one station only. In order to assist real-time video traffic to overcome short-term channel failures and to minimize video quality damage, we present the p-persistent queue management policy and propose a strategy for adaptive tuning the values of probabilities p assigned to queued packets.

Analysis of algorithms for decentralized dynamic channel resource reservation for data streaming in Wi-Fi networks

In this paper, we study a class of algorithms for decentralized dynamic resource reservation in Wi-Fi networks in which each station chooses and reserves time intervals for future transmission. To avoid interference, information on reserved time intervals is regularly sent to neighboring stations. To minimize the amount of transmitted control information, the reserved intervals are strictly periodic and have the same duration. We have developed two algorithms for decentralized resource reservation and have proven by mathematical modeling that these algorithms require smaller channel resource for streaming variable bitrate flows with given quality of service requirements than the existing algorithm. The developed algorithms can be used to allocate resource among base stations in dense infrastructure networks and among mesh-stations in selforganizing Wi-Fi networks.

Analytical model of a P-persistent method of queue management for multimedia streaming over wireless networks

On the transmission of several streams to different recipients over a wireless network in the case of degradation of the link quality with any of them, the head-of-line-blocking problem arises. This problem is especially important in the case of streaming with strict requirements to the quality of service. One of promising solution of this problem is the use of the P-persistent policy of queue management. In this work, an analytical model of such policy is proposed, making it possible to confirm the efficiency of this policy for preventing the head-of-line blocking and find the optimal values of its parameters.