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.

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This paper presents a performance analysis of the Temporally Ordered Routing Algorithm (TORA) protocol on top of IEEE 802.11a. IEEE 802.11a offers up to eight different coding schemes. Depending on the coding schemes the ad hoc routing behaviour differs. This paper describes the influence of the coding schemes, reviews the TORA protocol including the link reversal algorithm and presents the combined results. This research focuses on the application of TORA in a scenario where an ad hoc network is connected to the internet using an ad hoc gateway. Special emphasis was spent to a separated investigation of the protocol performance for uplink and downlink routes. The paper presents three enhancements to TORA avoiding and finding loops. Simulation results are presented showing the performance of TORA on top of IEEE 802.11a and describing the feasibility of TORA to be used as routing protocol in ad hoc integration scenarios.

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This paper discusses the role of ad hoc networking in future wireless communications. Ad hoc networks are'classified as isolated ad hoc networks with large and small sizes, integrated ad hoc networks in various scenarios and cellular ad hoc networks for the future mobile access networks. The very low traffic performance of large scale ad hoc networks is shown by simulation results, indicating such a kind of networks having little commercial potential Small size ad hoc networks seem to be ubiquitous because of the availability of cheap wireless LAN technologies. Integration of small size ad hoc networks with the global Internet can be realized by ad hoc gateways, that areproposed in this paper. In contrast to large scale isolated ad hoc networks, traffic performance of a cellular ad hoc network is very promising, indicating that cellular ad hoc networking seems to be a promising solution to fulfill the requirements of future wireless communication systems.