Analysis of QoS Requirements for e-Health Services and Mapping to Evolved Packet System QoS Classes

E-Health services comprise a broad range of healthcare services delivered by using information and communication technology. In order to support existing as well as emerging e-Health services over converged next generation network (NGN) architectures, there is a need for network QoS control mechanisms that meet the often stringent requirements of such services. In this paper, we evaluate the QoS support for e-Health services in the context of the Evolved Packet System (EPS), specified by the Third Generation Partnership Project (3GPP) as a multi-access all-IP NGN. We classify heterogeneous e-Health services based on context and network QoS requirements and propose a mapping to existing 3GPP QoS Class Identifiers (QCIs) that serve as a basis for the class-based QoS concept of the EPS. The proposed mapping aims to provide network operators with guidelines for meeting heterogeneous e-Health service requirements. As an example, we present the QoS requirements for a prototype e-Health service supporting tele-consultation between a patient and a doctor and illustrate the use of the proposed mapping to QCIs in standardized QoS control procedures

Conveying and Handling Location Information in the IP Multimedia Subsystem

The IP Multimedia Subsystem (IMS), specified by the 3rd Generation Partnership Project (3GPP), is a key element in the next-generation network (NGN) converged architecture. Extending the IMS towards provisioning support for location based services (LBS) will enable enhanced services and offer new revenues to the operator. Conveying location information in the IMS and connecting the IMS with a positioning system are still open issues. This paper presents the design and implementation of an IMS Location Server (ILS) integrating IMS with a positioning system. From the IMS perspective, the ILS serves as a service enabler for LBS. In order to demonstrate proof-of-concept in enhancing IMS-based services, two prototype service scenarios have been implemented: Location-aware Messaging (LaM), and Location-aware Push-to-Talk over cellular (LaPoC). Some work has been done by the IETF in the area of location information transport based on the Session Initiation Protocol (SIP). This paper proposes improvements in this area, primarily related to reducing the necessary amount of signaling with the specification of a new type of location filter. We have conducted measurements in a laboratory environment in order to illustrate our proposed solution and verify the benefits compared to existing solutions in terms of traffic load and session establishment time. Furthermore, we present a case study integrating the ILS with the Ericsson Mobile Positioning System (MPS)

Analyzing the Effect of TCP and Server Population on Massively Multiplayer Games

Many Massively Multiplayer Online Role-Playing Games (MMORPGs) use TCP flows for communication between the server and the game clients. The utilization of TCP, which was not initially designed for (soft) real-time services, has many implications for the competing traffic flows. In this paper we present a series of studies which explore the competition between MMORPG and other traffic flows. For that aim, we first extend a source-based traffic model, based on player’s activities during the day, to also incorporate the impact of the number of players sharing a server (server population) on network traffic. Based on real traffic traces, we statistically model the influence of the variation of the server’s player population on the network traffic, depending on the action categories (i.e., types of in-game player behaviour). Using the developed traffic model we prove that while server population only modifies specific action categories, this effect is significant enough to be observed on the overall traffic. We find that TCP Vegas is a good option for competing flows in order not to throttle the MMORPG flows and that TCP SACK is more respectful with game flows than other TCP variants, namely, Tahoe, Reno, and New Reno. Other tests show that MMORPG flows do not significantly reduce their sending window size when competing against UDP flows. Additionally, we study the effect of RTT unfairness between MMORPG flows, showing that it is less important than in the case of network-limited TCP flows

Design and Evaluation of a Multi-User Virtual Audio Chat, to appear in Future Generation Computer Systems, 2003. Accepted for publication

Abstract – As advanced Internet services, networked virtual reality applications impose certain Quality of Service (QoS) requirements, due to rich multimedia content and perceived “real-time” interactivity. Two different representations of QoS are needed at the user/application level and at the communication level, which our approach attempts to relate using as a reference an interconnection model for networked virtual reality applications. We present the design and development of a multi-user virtual audio chat application and a performance evaluation based on QoS requirements. Objective and subjective methods for determining QoS have been addressed, and our results analysed for the purpose of possible QoS improvements

A Review of Networked Multi-User Virtual Environments

Maturing and synergy of virtual reality and networking technologies have provided a basis for virtual environments distributed over the communication network. Such systems may be utilized to enable multiple users from distributed locations to interact in shared virtual worlds. The purpose of this report is to identify main developments in networked multi-user virtual environments, and describe the current trends in solving related problems. Selected virtual environments, including collaborative work virtual environments, distributed interactive simulation, and distributed virtual environments have been reviewed. Based on the review of virtual environments, main problems related to multiuser support and networking are identified and different approaches are compared and discussed. Keywords -- virtual reality, virtual environment, distributed interactive simulation, networking, multi-user, multicast Acknowledgement: This work has been partially supported by a DoE Research Grant, DAMA R-2..

Data Traffic Monitoring and AnalysisFrom Measurement, Classification, and Anomaly Detection to Quality of Experience /

XVI, 359 p. 121 illus.online resource