Dmitry Sivchenko

IPTV Systems, Standards and Architectures: Part II - IPTV Services over IMS: Architecture and Standardization

This article presents an architecture to support IPTV services in an IMS-based NGN. The architecture extends the current IMS specification with the required functionality to meet additional requirements of IPTV services. The proposed architecture can be deployed by an IPTV provider over heterogeneous access networks (mobile, wireless, and fixed) as a part of standardized NGN solutions. After presenting an overview of the IPTV standardization activities in DVB, ITU-T, ETSI, ATIS, 3GPP, and OMA, this article focuses on the ETSI TISPAN IPTV standardization. IMS-based IPTV architectural functions and possible IPTV evolutionary steps are discussed, and then the article presents an implementation example.

IMS based IPTV services: architecture and implementation

This paper presents a novel architecture for providing converged IP-based TV (IPTV) services specified by ETSI TISPAN standardisation for IPTV in ongoing NGN release 2 specifications. The described IPTV architecture is based on utilisation of the IP Multimedia Subsystem concept used by NGN architectural framework and its adaptation to provide the IPTV specific functionalities and services. Using the foundation provided by the IMS based architecture, we propose a new functional architecture to enhance the functionalities and features needed for scalable converged networks, flexible media delivery and advanced IPTV service scenarios. The proposed architecture, leveraging on the FMC architecture that operators may deploy to provide IPTV service across different access networks in future deployments (mobile, wireless, fixed) has prototypically been implemented in the ScaleNet* demonstrator testbed. This paper analyses in detail the main principles for such a converged reference architecture. The paper also presents the IPTV service scenario prototype called Click-to-Multimedia which shows some basic features and advantages implemented on top of the presented architecture by prototyping demo applications as proof of concept reference.

Energy optimisation in heterogeneous multi-RAT networks

To be able to serve the traffic demand in todays mobile networks, more than 123.000 base stations (BSs) have been deployed by the different network providers in Germany. These BSs are working 24/7 and are dimensioned to serve capacity demand during busy hours. Currently no mechanisms for a load adaptive network reconfiguration are implemented. As a result, much energy is wasted during times in which the capacity demand is low. This paper describes an adaptive, context-aware, and technology-comprehensive system architecture for power management in modern radio networks. The results presented are developed within the project Communicate Green (ComGreen). A major goal of ComGreen is the development of a testbed in order to investigate and demonstrate the main achievements of the project. The aim of this paper is twofold: First, it highlights the ComGreen concepts for power management in heterogeneous radio networks. Second, a detailed description of the testbed is provided.

FUZPAG: A fuzzy-controlled packet aggregation scheme for wireless mesh networks

Wireless mesh networks (WMNs) are wireless multi-hop backhaul networks in which mesh routers relay traffic on behalf of clients or other routers. Due to large MAC layer overhead, applications such as Voice over IP, which send many small packets, show poor performance in WMNs. Packet aggregation increases the capacity of IEEE 802.11-based WMNs by aggregating small packets into larger ones and thereby reducing overhead. In order to have enough packets to aggregate, packets need to be delayed and buffered. Current aggregation mechanisms use fixed buffer delays or do not take into account the delay characteristics of the saturated IEEE 802.11 MAC layer. In this work, we present FUZPAG, a novel packet aggregation architecture for IEEE 802.11-based wireless mesh networks. It uses fuzzy control to determine the optimum aggregation buffer delay under the current channel utilization. By cooperation among neighboring nodes FUZPAG distributes the buffer delay in a fair way. We implemented and evaluated the system in a wireless mesh testbed. For different network topologies we show that FUZPAG outperforms standard aggregation in terms of end-to-end latency under a wide range of traffic patterns.

Integrated mobility and resource management for cross-network resource sharing in heterogeneous wireless networks using traffic offload policies

The problem of efficient use of resources in wireless access networks becomes critical today with users expecting continuous high-speed network access. While access network capacity continues to increase, simultaneous operation of multiple wireless access networks presents an opportunity to increase the data rates available to end-users even further using intelligent cross-network resource sharing. This paper introduces a new integrated mobility and resource management (IMRM) framework for automatic execution of policies for cross-network resource sharing using traffic offload and pre-emptive resource reservation algorithms. The presented framework enables both mobile-initiated and network-initiated resource sharing policies to be executed. This paper presents the framework in detail and analyses its performance using extensive ns-2 simulations of the operation of a set of static policies based on measured signal strength, and dynamic pre-emptive network-initiated policies in a WiFi/WiMAX scenario. The detailed evaluation of the static policies clearly shows that the quality of voice applications shows large deviation, mostly due to very different levels of delay in access networks. Based on these conclusions, this paper presents a design of two new dynamic policies and shows that such policies, when efficiently implemented using the new IMRM framework can greatly improve the capacity of the network to serve voice traffic with a minimal impact on the data traffic and with a very low signalling overhead.

Broadband wireless service provisioning through a wireless mesh backhaul

This paper describes results achieved within recently successfully completed EU projects CARMEN (CARrier grade MEsh Networks) and PANLABII (PAN European LABoratory for next generation networks and services). The main contribution of the CARMEN project is the design and prototype of a wireless mesh network that allows quality of service provisioning. Currently, CARMEN functionalities are evaluated using a 9-node mesh testbed. However, thanks to the PANLABII project, which develops a federation platform for independent distributed testbeds, now, CARMEN functions can be tested in various network environments and under different traffic conditions. Through such performance evaluation versatility, it becomes possible to prove the scalability and efficiency of mesh technology for providing broadband services.

On the Performance of Enhanced Hierarchical Mobile IPv6

This paper defines a multi-hierarchical architecture of mobile anchor points (MAP) in a micro mobility network to enhance the performance of hierarchical mobile IPv protocol. By deploying this multi-hierarchical architecture of MAPs the latency of IP handoffs is reduced significantly so that the traffic performance during handoffs can be improved. For this purpose a new multi-binding update signalling packet is developed to accelerate the handoff process using a new registration mechanism, with which the MAP can forward the multi-binding update message to the next hierarchical MAP level. The acknowledgement message for the multi-binding update message will be sent by the last MAP or the home agent. Moreover, a modified function for processing the data packets destined to mobile nodes is introduced in MAPs so that the packet overhead can still keep small by avoiding multi-tunnelling that can be resulted from the multi-hierarchy of MAPs without this modification. The investigated proposal is implemented in NS2 and the improvements of the traffic performance are verified by the simulation results

Dynamic channel bundling in 802.11a based media-transport mesh networks

Most 802.11 WirelessLAN media transport networks communicate on a shared channel. Since bandwidth- and QoS-demands of new media content constantly increase, network capacities tend to be bailed out soon, if the entire WLAN spectrum is not efficiently exploited. The proposed multi-layer approach combines dynamic channel distribution with additional dynamic interface bundling for multi-interface mesh networks used for media transport. This novel distributed channel utilization scheme aims for a better support of QoS-related traffic as well as traffic on prioritized (gateway) routes in such networks.

Bandwidth Sensitive Adaptation of Applications during MRM Controlled Multi-Radio Handover

In heterogeneous radio access networks mobile terminals can dynamically change their radio access not only between access points but also between different radio access technologies (RATs). We present a network based Multi-Radio Management (MRM) for seamless control of inter-RAT mobility. Access Selection can be triggered by a change of radio channel quality, by the start of an application or by system load and handover is executed by enhanced MobileIPv6. Dynamic adaptation of the IMS services, e.g. adaptation of IPTV to the available bandwidth, is realized by triggering additional mid-call SIP signaling between communicating parties so that Quality of Experience (QoE) can be significantly improved. The described MRM and dynamic adaptation of IMS services are validated by a prototypical implementation in an integrated demonstrator.

Integrated mobility and resource management mechanism for FMC networks

A network based method for an intelligent distribution of transport resources of heterogeneous points of attachment to the network among mobile nodes with multiple network interfaces is presented in this paper. Selection of the used network for a particular multimedia session is based on the QoS situation in access networks available for mobile nodes. A possible realisation using IP multimedia subsystem on the signalling plane is described. The proposed idea is based on the fixed & mobile converged network architecture with Ethernet based data transmission developed in the ScaleNet* project. The performance of the presented mechanism has been evaluated by computer simulation.