Networking with VSATs - From low bit rate systems to ATM service provision

Very Small Aperture Terminal (VSAT) satellite networks have so far been successful in the provision of specific communication services to geographically dispersed users. However, VSAT networks are expected to provide a much wider range of services (voice, data, and multimedia). We investigate how this service integration could be achieved and show that performance improvements are possible if efficient multiaccess protocols and speech compression with voice activity detection techniques are used. We also discuss the role of VSATs in the provision of access for remote users to the Integrated Broadband Communications Network. The need for optimization of the channel capacity allocation scheme is discussed, using a preliminary performance analysis for a Dynamic Reservation TDMA system which takes advantage of the flexibility and the statistical multiplexing capabilities of ATM and supports various VBR and CBR services. Some bottlenecks, introduced by the satellite link, in the performance of protocols such as TCP/IP are highlighted. It is shown that it could be possible to use VSATs for ATM service, but there are limitations on the system's performance from the satellite delay and limited link capacity. (Author)

[1]  Nedo Celandroni,et al.  The FODA-TDMA satellite access scheme: presentation, study of the system, and results , 1991, IEEE Trans. Commun..

[2]  G. A. Awater,et al.  ATM and Aloha-common performance models , 1994, 1994 IEEE GLOBECOM. Communications: The Global Bridge.

[3]  Gerard Maral,et al.  A dynamic allocation protocol for a satellite network integrated with a B.ISDN , 1992 .

[4]  Dipankar Raychaudhuri.  Stability, Throughput, and Delay of Asynchronous Selective Reject ALOHA , 1987, IEEE Trans. Commun..

[5]  J. Gruber,et al.  A Comparison of Measured and Calculated Speech Temporal Parameters Relevant to Speech Activity Detection , 1982, IEEE Trans. Commun..

[6]  Manfred R. Schroeder,et al.  Code-excited linear prediction(CELP): High-quality speech at very low bit rates , 1985, ICASSP '85. IEEE International Conference on Acoustics, Speech, and Signal Processing.

[7]  Dipankar Raychaudhuri.  Selective reject ALOHA/FCFS: An advanced VSAT channel access protocol , 1989 .

[8]  Raif O. Onvural,et al.  Asynchronous Transfer Mode Networks: Performance Issues, Second Edition , 1993 .

[9]  D. S. Gokhale,et al.  Asynchronous transfer mode (ATM) operation via satellite: issues, challenges and resolutions , 1994 .

[10]  Paul T. Brady,et al.  A statistical analysis of on-off patterns in 16 conversations , 1968 .

[11]  Barry G. Evans,et al.  Broadband Island interconnection via satellite-performance analysis for the race II-catalyst project , 1994 .

[12]  C. Weinstein,et al.  Fractional Speech Loss and Talker Activity Model for TASI and for Packet-Switched Speech , 1978, IEEE Trans. Commun..

[13]  P. Polese,et al.  Satellites in UMTS and B-ISDN: status of activities and perspectives , 1994 .

[14]  B. G. Evans,et al.  A high quality voice coder with integrated echo canceller and voice activity detector for VSAT systems , 1993 .

[15]  M. Fischer.  Data Performance in a System Where Data Packets are Transmitted During Voice Silent Periods - Single Channel Case , 1979, IEEE Transactions on Communications.

[16]  Dipankar Raychaudhuri,et al.  Ku-Band satellite data networks using very small aperture terminals—part I: Multi-access protocols , 1987 .

[17]  F. P. Coakley,et al.  Adaptive multiple access protocols for VSATs providing voice/data services and ATM interconnection , 1995 .

[18]  J. Gruber,et al.  Delay Related Issues in Integrated Voice and Data Networks , 1981, IEEE Trans. Commun..

[19]  J. Massey.  Collision-Resolution Algorithms and Random-Access Communications , 1981 .

[20]  Barry G. Evans,et al.  Multi-access protocols for a multiservice VSAT network , 1994, Proceedings of ICC/SUPERCOMM'94 - 1994 International Conference on Communications.