화학공학소재연구정보센터
Automatica, Vol.40, No.5, 729-741, 2004
Design of a bandwidth-on-demand (BoD) protocol for satellite networks modelled as time-delay systems
Bandwidth-on-demand (BoD) access protocols address the problem of guaranteeing a high exploitation of the valuable satellite bandwidth in the presence of large amount of data traffic accessing the satellite network. The novelty of the proposed BoD scheme consists in the use of control theory concepts to model the satellite network as a time-delay system and to generate the bandwidth requests. The proposed scheme, based on the internal model control and on the Smith's principle, yields the following advantages: (i) when the network is not congested, it provides upper-bounds to the queue lengths and to the queuing delays of the satellite terminal buffers; (ii) it is capable of recovering from congested states; (iii) it is independent of the statistical characteristics of the traffic entering the satellite network; (iv) the requests are such that the satellite terminals have always enough traffic to use all the requested bandwidth (so that no bandwidth is wasted). The paper includes simulations showing the effectiveness of the proposed BoD scheme. The work underlying this paper has been performed within the GEOCAST project belonging to the fifth framework Information Society and Technology programme of the European Union. (C) 2003 Elsevier Ltd. All rights reserved.