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A multi-layered satellite network (MLSN) appears to be a promising network for providing global ubiquitous broadband communication. To utilize the abundant network resources of the MLSNs, fair traffic distribution among its satellite layers is, indeed, important. In this paper, we propose a routing method to optimally distribute traffic load among the layers (i.e., the satellite layers in the MLSN). The load balancing scheme of the proposed routing method is developed by adopting a traffic distribution model, which is based upon network capacity estimation and theoretical analysis of the congestion rate in each layer. The performance of the proposed routing method has been validated through extensive computer simulations, which demonstrate that our traffic distribution model is reliable enough to characterize the traffic behavior in the MLSN. Furthermore, in contrast with the basic routing approach, our proposed routing method is more effective in terms of improved throughput and lower packet drops, which are optimized by the theoretical parameter setting. [ABSTRACT FROM PUBLISHER]

In 1993, a proposal at the Japan-US Science, Technology, and Space Applications Program (JUSTSAP) workshop led to a subsequent series of satellite communications experiments and demonstrations, under the title of Trans-Pacific High Data Rate Satellite Communications Experiments. The first phase of which was a joint collaboration between government and industry teams in the United States and Japan that successfully demonstrated distributed high definition video (HDV) post-production on a global scale using a combination of high data rate satellites and terrestrial fiber optic asynchronous transfer mode (ATM) networks. This was followed by the Phase-2 Internet Protocol (IP) based experiments and demonstrations [4–6] in tele-medicine and distance education, using another combination of two high data rate satellites and terrestrial fiber optic networks. The Visible Human tele-medicine and Remote Astronomy distance education demonstrations and their use of distributed systems technologies afforded an opportunity for people around the world to work together as a virtual team under one roof, using resources thousands of miles away as if they were next to each other. The visible human activity demonstrated global-scale interactive biomedical image segmentation, labeling, classification, and indexing using large images; the remote astronomy activity demonstrated collaborative observation and distance education at multiple locations around the globe and the transparent operations of distributed systems technologies over a combination of broadband satellites and terrestrial networks. The use of Internet Protocol related technologies allowed the general public to be an integral part of the exciting activities, helped to examine issues in constructing a global information infrastructure with broadband satellites, and afforded an opportunity to tap the research results from the (reliable) multicast and distributed systems communities. This paper summarizes the Phase-2... [ABSTRACT FROM AUTHOR]

A high data rate (HDR) satellite communication system is essential for developing the network configuration of a Global Information Infrastructure (GII) because of its features, such as wide area coverage, flexibility of network configuration and multicast connection capability. From this point of view, Communications Research Laboratory (CRL) is conducting research and development of a Gigabit satellite system [1] that has an on-board ATM switch and gigabit-class capacity. We have developed a hardware simulator in order to investigate how satellite links influence on-board ATM switching and network performance, such as a long delay and burst error. In this paper, we describe the simulation results for the TCP layer performance and the SVC connection set-up performance. [ABSTRACT FROM AUTHOR]

Abstract: WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided. [Copyright &y& Elsevier]