@inproceedings {Simula.ND.111,
	title = {Evaluation of Multi-Core Scheduling Mechanisms for Heterogeneous Processing Architectures},
	journal = {Network and Operating System Support for Digital Audio and Video (NOSSDAV 2008)},
	year = {2008},
	month = {May},
	pages = {33-38},
	publisher = {ACM},
	type = {Workshop},
	abstract = {General-purpose CPUs with multiple cores are established products, and new heterogeneous technology like the Cell broadband engine and general-purpose GPUs bring an even higher degree of true multi-processing into the market. However, means for utilizing the processing power is immature. Current tools typically assume that exclusive use of these resources is sufficient, but this assumption will soon be invalid because the interest in using their processing power for general-purpose tasks. Among the applications that can benefit from such technology is transcoding support for distributed media applications, where remote participants join and leave dynamically. Transcoding consists of several clearly separated processing operations that consume a lot of resources, such that individual processing units are unable to handle all operations of a session of arbitrary size. The individual operations can then be distributed over several processing units, and data must be moved between them according to the dependencies between operations. Many multi-processor scheduling approaches exist, but to the best of our knowledge, a challenge is still to find mechanisms that can schedule dynamic workloads of communicating operations while taking both the processing and communication requirements into account. For such applications, we believe that feasible scheduling can be performed in two levels, i.e., divided into the task of placing a job onto a processing unit and the task of multitasking time-slices within a single processing unit. We have implemented some simple high-level scheduling mechanisms and simulated a video conferencing scenario running on topologies inspired by existing systems from Intel, AMD, IBM and nVidia. Our results show the importance of using an efficient high-level scheduler.},
	isbn = {978-1-60588-157-6},
	author = {H{\r a}kon Kvale {Stensland} and Griwodz, Carsten and Halvorsen, P{\r a}l},
	editor = {Griwodz, Carsten and Wolf, Lars}
}
@book {Simula.ND.283,
	title = {Proceedings of the 18th International Workshop on Network and Operating Systems Support for Digital Audio and Video (NOSSDAV)},
	year = {2008},
	month = {May},
	publisher = {ACM},
	abstract = {The 18th Annual International Workshop on Network and Operating Systems Support for Digital Audio and Video was held at TU Braunschweig, the oldest technical university in Germany. As always at NOSSDAV, new and controversial ideas and approaches were presented and discussed, and young and experienced researchers met for lively discussions. To strengthen this aspect of the workshop, we arranged NOSSDAV 2008 under the dual sign of interactivity. Firstly, we particularly encouraged submissions to the topic of system support for interactive multimedia, and of course, we expected the intense discussions that are usual for NOSSDAV and set it apart from many other conferences and workshops. As promised in the call-for-papers, interactivity plays a major role in many of the papers presented at this year{\textquoteright}s NOSSDAV. Secondly, we had a separate call for demonstrators of research systems and prototypes. This results in a strong demonstration program that allows participants to see and interact with research systems and prototypes in practice. Overall, the workshop featured the presentations of 17 research papers by authors and presenters from 16 countries. The paper topics include network and operating system support, new use of multimedia services, the understanding of multimedia workload and streaming with specific environments or applications. Furthermore, a dozen prototypes and systems are exhibited in the demonstration session. Moreover, NOSSDAV 2008 comprises a strong invited program as well. The keynote speech of NOSSDAV 2008 will be given by Professor J{\"o}rg Liebeherr, University of Toronto. In his keynote entitled "Overlays can do more ... if not everything", he claims that the fundamental limits of overlay networking remain largely unexplored, and presents the challenges of large numbers of co-existing overlays. The invited talk by Paulo Mendes of INESC entitled "Cooperative Networking as Boosting Tool for Internet Interactivity" will show us that cooperative networking appears at several layers of the network stack and start a discussion on conditions for successful or failing systems.},
	isbn = {978-1-60588-157-6},
	author = {Griwodz, Carsten and Wolf, Lars}
}
@inproceedings {Simula.ND.112,
	title = {TCP Enhancements for Interactive Thin-Stream Applications},
	journal = {Network and Operating Systems Support for Digital Audio and Video (NOSSDAV 2008)},
	year = {2008},
	note = {short paper and demo},
	month = {May},
	pages = {127-128},
	publisher = {ACM},
	type = {Workshop},
	abstract = {TCP is frequently used for interactive multimedia applications like online games and voice-over-IP (VoIP) due to firewall issues and fairness considerations. However, traffic analysis shows that these streams usually have small packets and a low packet rate, and that in case of loss, severe latency penalties occur for all existing TCP variations in Linux. In this demonstration, we show how small, efficient TCP enhancements greatly improve the perceived quality of such low latency, interactive applications.},
	isbn = {978-1-60588-157-6},
	author = {Petlund, Andreas and Evensen, Kristian and Griwodz, Carsten and Halvorsen, P{\r a}l},
	editor = {Griwodz, Carsten and Wolf, Lars}
}
@inproceedings {Simula.ND.117,
	title = {Transparent Protocol Translation and Load Balancing on a Network Processor in a Media Streaming Scenario},
	journal = {Network and Operating System Support for Digital Audio and Video (NOSSDAV 2008)},
	year = {2008},
	month = {May},
	pages = {129-130},
	publisher = {ACM},
	type = {Workshop},
	abstract = {Today, major newspapers and TV stations make live and on-demand audio/video content available, video-on-demand services are becoming common and even personal media are frequently uploaded to streaming sites. The discussion about the best transport protocol for streaming has been going on for years. Currently, HTTP-streaming is usual although the transport of streaming media data over TCP is hindered by TCP{\textquoteright}s probing behavior, which results in the rapid reduction and slow recovery of the packet rates. On the other hand, UDP has been criticized for being unfair against TCP, and it is therefore often blocked by access network providers. To exploit benefits of both TCP and UDP, we have implemented a proxy that performs transparent protocol translation in such a way that the video stream is delivered to clients in a TCP-compatible and TCP-friendly way, but with UDP-like smoothness. The translation is related to multicast-to-unicast translation and to voice-over-IP proxies that translate between UDP and TCP. Furthermore, it is also similar to the use of proxy caching that ISPs employ to reduce bandwidth demands. The unique advantage of our approach is that we avoid full-featured TCP handling on the proxy server but still achieve live protocol translation at line-speed in a TCP-compliant, TCP-friendly manner. Although we discard packets just like a sender of non-adaptive video over TCP, we achieve higher user-perceived quality because our proxy can avoid receive queue underflows in the proxy, while also achieving the same average bandwidth as a TCP connection between proxy and client. In this demo, we present our prototype implemented on an Intel IXP2400 network processor. The prototype proxy does not buffer outgoing packets, yielding data loss in case of a congested TCP side. Comparing HTTP-streaming from a web-server and RTP/UDP-streaming from a video server shows that, in case of some loss, our solution using UDP from the server and a proxy that translates to TCP delivers a smoother stream at playout rate while the end-to-end TCP stream oscillates heavily.},
	isbn = {978-1-60588-157-6},
	author = {Espeland, H{\r a}vard and Carl Henrik {Lunde} and H{\r a}kon Kvale {Stensland} and Griwodz, Carsten and Halvorsen, P{\r a}l},
	editor = {Griwodz, Carsten and Wolf, Lars}
}
@inproceedings {cossmann-1996,
	title = {Interoperable ITV Systems Based on MHEG},
	journal = {Proceedings of SPIE/ACM Conference on Multimedia Computing and Networking (MMCN)},
	volume = {2667},
	number = {1},
	year = {1996},
	month = {jan},
	pages = {60-68},
	publisher = {SPIE},
	type = {Annual},
	abstract = {Today{\textquoteright}s interactive television systems are using proprietary communication protocols and interchange formats. To provide inter-operability at the application level the next generation of interactive television system will be based on standardized communication protocols, monomedia and multimedia formats. This paper presents the Globally Accessible Services (GLASS) system which is a prototype interactive television system based on the Multimedia and Hypermedia Expert Group (MHEG) standard. After a brief introduction to MHEG as the multimedia interchange format between application server and set-top box in interactive television systems, the GLASS clients and servers are described, and an example scenario for navigation in the GLASS system is provided.},
	isbn = {9780819420411},
	doi = {http://dx.doi.org/10.1117/12.235895},
	author = {Cossmann, Helmut and Griwodz, Carsten and Grassel, Guido and P{\"u}hlh{\"o}fer, Michael and Schreiber, Matthias and Steinmetz, Ralf and Wittig, Hartmut and Wolf, Lars},
	editor = {Freeman, Martin and Jardetzky, Paul and Harrick M. {Vin}}
}
@inproceedings {Cossmann.1995.1,
	title = {GLASS: a Distributed MHEG-Based Multimedia System},
	journal = {COST 237 Workshop},
	year = {1995},
	month = {nov},
	pages = {61-78},
	publisher = {Springer-Verlag},
	type = {Annual},
	isbn = {3-540-61028-6},
	author = {Cossmann, Helmut and Griwodz, Carsten and Grassel, Guido and P{\"u}hlh{\"o}fer, Michael and Schreiber, Matthias and Steinmetz, Ralf and Wittig, Hartmut and Wolf, Lars},
	editor = {Hutchison, David and Christiansen, Henning and Coulson, Geoff and Andr{\'e} A. S. {Danthine}}
}
