VSAT data networks
Article Abstract:
ALOHA and CDMA are the two general methods used to provide random access packet communications in very small aperture (VSAT) data networks. A VSAT data network architecture is almost always designed so that a single large earth station, the hub, transmits data in a broadcast channel to a large number of VSATs. The key decision in the overall design of the network is the choice of an access technique for the VSAT-to-hub multiple-access channel. The two primary access techniques used to share the high capacity of a typical commercial satellite transponder among a number of earth stations are frequency-division multiple access and time-division multiple access. The ALOHA form of multiple access also requires the bandwidth of the channel to be greater than the information bandwidth that corresponds to the average data rate transmitted from any single user in the channel. The signals in the low duty cycle ALOHA channel can be modified by spreading the packets out in time so that the disadvantage of high peak power is eliminated and the signal quality remains unchanged. This is called spread ALOHA.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1990
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Rationale, directions, and issues surrounding high speed networks
Article Abstract:
Networking is an integral part of computing and there is a growing need for high speed local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). The requirements of these networks are being developed around a fiber optic transmission base. The growth of networks, the evolving power of devices attached to the network, aggressive application processing, and decreasing costs contribute to the need for higher speed networks. There are obstacles that do not let applications use the entire bandwidth of any network media, such as the need for network management and traffic control. High speed networks need standards, but the standards development process is slow and always involves compromises. User demands and technological advances are driving the development of high speed communication networks. Lightwave technologies and new network architectures are being combined to provide high speed networks.
Publication Name: Proceedings of the IEEE
Subject: Electronics
ISSN: 0018-9219
Year: 1990
User Contributions:
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