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Full-Text Articles in Physical Sciences and Mathematics
Distributed Server Delivery Of Immersive Voip Service: Balancing Between Voice Latency And Access Upload Cost, Ying Peng Que, Farzad Safaei, P. Boustead
Distributed Server Delivery Of Immersive Voip Service: Balancing Between Voice Latency And Access Upload Cost, Ying Peng Que, Farzad Safaei, P. Boustead
Paul Boustead
As a future communication tool to the Distributed Virtual Environment, the Immersive VoIP service delivers to each user a real-time mix of nearby user voices which are all rendered according to their respective virtual world positions. In this work, we conjecture that the voice latency constraints between Immersive VolP users would vary according to their virtual world distance of separation. As verified in our subjective listening tests, this conjecture is more realistic than fixed latency constraint, in terms of user perceptual experience and network feasibility. Empowered by the Bandwidth Reduced server assignment algorithm, the proposed two-hop distributed server architecture achieves …
Latency And Scalability: A Survey Of Issues And Techniques For Supporting Networked Games, Xinbo Jiang, Farzad Safaei, P. Boustead
Latency And Scalability: A Survey Of Issues And Techniques For Supporting Networked Games, Xinbo Jiang, Farzad Safaei, P. Boustead
Paul Boustead
The popularity of on-line games that emphasize real-time interactivity is on the rise. A survey of issues and techniques for supporting on-line games is provided in this paper. Latency and scalability are two primary aspects on which this survey is based. Network latency heavily influences the design of on-line games with regards to the nature of interactivities involved, as well as, real-time flows such as voice and video if enhanced user immersive experiences are required. As a consequence, a trade-off between consistency and responsiveness, the two latency-related artifacts, is usually needed. This can be demonstrated through a number of latency …
A Hybrid Optical Network Architecture Consisting Of Optical Cross Connects And Optical Burst Switches, Chuntung Chou, Farzad Safaei, P. Boustead, I. Ouveysi
A Hybrid Optical Network Architecture Consisting Of Optical Cross Connects And Optical Burst Switches, Chuntung Chou, Farzad Safaei, P. Boustead, I. Ouveysi
Paul Boustead
Optical burst switches (OBSes) have been proposed to improve the utilization of a network of optical cross connect (OXCs). Current studies on OBS assume a network consisting of OBSes alone. While this is a reasonable assumption for evaluating a new technology, the question of how a network of OXCs can be evolved to a network of OBSes has not been studied. In this paper, we propose a hybrid architecture consisting of OBSes at the network edge and OXCs in the network core. This architecture allows carriers to gradually migrate from an OXC-based network to an OBS-based network with an improved …
Dice: Internet Delivery Of Immersive Voice Communication For Crowded Virtual Spaces, P. Boustead, Farzad Safaei, M. Dowlatshahi
Dice: Internet Delivery Of Immersive Voice Communication For Crowded Virtual Spaces, P. Boustead, Farzad Safaei, M. Dowlatshahi
Paul Boustead
This paper develops a scalable system design for the creation, and delivery over the Internet, of a realistic voice communication service for crowded virtual spaces. Examples of crowded spaces include virtual market places or battlefields in online games. A realistic crowded audio scene including spatial rendering of the voices of surrounding avatars is impractical to deliver over the Internet in a peer-to-peer manner due to access bandwidth limitations and cost. A brute force server model, on the other hand, will face significant computational costs and scalability issues. This paper presents a novel server-based architecture for this service that performs simple …
Provisioning Content Distribution Networks Over Shared Infrastructure, T. V. Nguyen, Chuntung Chou, P. Boustead
Provisioning Content Distribution Networks Over Shared Infrastructure, T. V. Nguyen, Chuntung Chou, P. Boustead
Paul Boustead
The current paradigm of content distribution networks (CDN) deployment requires heavy infrastructure investment since a large number of servers have to be deployed over a wide area. To overcome this difficulty, we propose a new paradigm where future CDNs are to be deployed over a leased server infrastructure. This paradigm shift changes the object placement problem in current CDNs to a combined object placement and resource provisioning problem. In this paper, we present a formulation of this problem, which is a combinatorial optimization, and prove its NP-hardness. We also present a heuristic solution to this problem based on Lagrangian relaxation …
Tcmca: A Source-Based Distributed Topology Control Algorithm For Mission Critical Applications In Mobile Ad-Hoc Networks, G. Srivastava, P. Boustead, Joe F. Chicharo, C. Ware
Tcmca: A Source-Based Distributed Topology Control Algorithm For Mission Critical Applications In Mobile Ad-Hoc Networks, G. Srivastava, P. Boustead, Joe F. Chicharo, C. Ware
Paul Boustead
Topology control in a wireless ad-hoc network allows better spatial reuse of the wireless channel and network resources. The existing topology control algorithms tend to optimise network power usage by keeping the topology connected but do not take the network application requirements into account. Mission critical applications which require explicit end-to-end bandwidth and delay guarantees may not find enough resources in the network with the existing network topology. We have devised a topology control algorithm for mission critical applications (TCMCA) in wireless ad-hoc networks, which adapts the network topology to improve the available resources for a set of mission critical …
Minimising The Computational Cost Of Providing A Mobile Immersive Communication Environment (Mice), Ying Peng Que, Paul Boustead, Farzad Safaei
Minimising The Computational Cost Of Providing A Mobile Immersive Communication Environment (Mice), Ying Peng Que, Paul Boustead, Farzad Safaei
Paul Boustead
This paper investigates the minimisation of the computational cost of providing Immersive Voice Communication (IVC) for mobile clients attached to a Distributed Virtual Environment (DVE). When experiencing IVC, each listening avatar in the DVE, receives a mix of the surrounding avatars’ voices, all rendered according to their respective positions in the virtual world. We propose to deliver our mobile IVC service using a type of server-based network architecture to perform voice spatialisation function and mixing for each mobile client. This model will minimise both the access bandwidth and processing power requirements of the mobile devices. We propose a model for …
An Architecture For Carrier Grade Programmable Networks, T. V. Nguyen, P. Boustead, Farzad Safaei
An Architecture For Carrier Grade Programmable Networks, T. V. Nguyen, P. Boustead, Farzad Safaei
Paul Boustead
Active and programmable networks allow innovative new services to be deployed rapidly. However, in a carrier grade network, it is imperative to maintain a scalable fast path mechanism so that the delay and throughput requirements are met. This is particularly important since, in many cases, network-level processing is only needed for a subset of packets and the remainder of traffic must be forwarded on the fast path. It is a challenge to design a cost effective node architecture that can satisfy this requirement. Current models are often 'revolutionary' and may not scale to the required performance levels of a carrier …
Ip Forwarding Alternatives In Cell Switched Optical Networks, P. Boustead, Joe F. Chicharo
Ip Forwarding Alternatives In Cell Switched Optical Networks, P. Boustead, Joe F. Chicharo
Paul Boustead
Optical switching will enable core Internet packet switching to scale with future transmission rate increases. Currently proposed optical ATM switches do not allow packet reassembly, which is necessary for packet level forwarding. This results in the requirement to create end to end ATM virtual connections for flows even if they contain only one packet. In electronically switched networks MPOA and MPLS allow both cell and packet level forwarding to overcome this problem. This paper examines the feasibility of implementing such protocols over an optically switched network. Two different architectures are examined: use of an adjunct electrical router; and native optical …
Managing Latency And Fairness In Networked Games, J. Brun, Farzad Safaei, P. Boustead
Managing Latency And Fairness In Networked Games, J. Brun, Farzad Safaei, P. Boustead
Paul Boustead
Networked games can be seen as forerunners of all kinds of participatory entertainment applications delivered through the Internet. Physically dispersed players are immersed in a common virtual environment where they interact in real time. When a user performs an action, other users must be made aware of that action. Otherwise, there is a discrepancy in the perceptions of participants about the overall state of the virtual world. This discrepancy could lead to undesirable and sometimes paradoxical outcomes. In particular, first-person shooter, and to a lesser extent role-playing games impose stringent constraints on responsiveness and consistency.
Performance Evaluation Of A Proxy System For Providing Immersive Audio Communication To Massively Multi-Player Games, C. D. Nguyen, Farzad Safaei, P. Boustead
Performance Evaluation Of A Proxy System For Providing Immersive Audio Communication To Massively Multi-Player Games, C. D. Nguyen, Farzad Safaei, P. Boustead
Paul Boustead
In this paper, a distributed proxy architecture is introduced for the provisioning of an immersive audio communication service to massively multi-player online games. The immersive audio communication service enables each avatar to hear a realistic audio mix of conversations in its hearing range. In our earlier work, peer-to-peer and central server architectures have been proposed for this service. In this paper, a distributed proxy architecture with either using network multicast or unicast between proxies is introduced to address the limitations of the previous architectures. The main focus of this paper is to evaluate the bandwidth cost saving of network multicast …
Latency-Driven Distribution: Infrastructure Needs Of Participatory Entertainment Applications, Farzad Safaei, P. Boustead, C. D. Nguyen, J. Brun, M. Dowlatshahi
Latency-Driven Distribution: Infrastructure Needs Of Participatory Entertainment Applications, Farzad Safaei, P. Boustead, C. D. Nguyen, J. Brun, M. Dowlatshahi
Paul Boustead
This article evaluates network and server infrastructure requirements to support real-time flows associated with networked entertainment applications. These include the state information flow to update the status of the virtual environment and immersive communication flows such as voice, video, gesture, and haptics communication. The article demonstrates that scaling these applications to large geographical spreads of participants requires distribution of computation to meet the latency constraints of the applications. This latency-driven distribution of computation is essential even when there are no limitations on the availability of computational resources in one location. The article provides detailed results on distributed server architectures for …
Investigation And Modeling Of Traffic Issues In Immersive Audio Environments, J. Mcmahon, M. Rumsewicz, P. Boustead, Farzad Safaei
Investigation And Modeling Of Traffic Issues In Immersive Audio Environments, J. Mcmahon, M. Rumsewicz, P. Boustead, Farzad Safaei
Paul Boustead
A growing area of technical importance is that of distributed virtual environments for work and play. For the audio component of such environments to be useful, great emphasis must be placed on the delivery of high quality audio scenes in which participants may change their relative positions. In this paper we describe and analyze an algorithm focused on maintaining relative synchronization between multiple users of such an environment and examine the subjective quality of service achieved.