摘要:

A distributed routing algorithm for an integrated network with circuit and packet switching capabilities is proposed. The algorithm is based on the ideas of a minimum-delay routing algorithm proposed by Gallager. The trunk organisation used in the integrated network allows a fixed or moving boundary between circuit and packet traffic. The proposed routing algorithm operates independently of the trunk management policy, and attempts to maximise a network performance measureM. This measure reflects both the end-to-end blocking for circuit traffic and the average end-to-end delay for packets. It will be shown that, for optimal performance, packet traffic must be routed in the direction of minimum incremental link delay to the packet destination. Circuit routing, on the other hand, depends on whether the trunk boundary is fixed or movable. Thus, under the fixed-boundary management policy, circuit traffic must be routed in the direction of minimum incremental link blocking to the circuit destination. Under the moving-boundary management policy, circuit routes must be chosen to minimise the effect on packet performance, i.e. minimum incremental packet delay due to incremental circuit traffic. The proposed routing algorithm has been tested for its adaptability to various load conditions. These investigations have also demonstrated the performance improvement due to the moving-boundary trunk organisation.

DOI:10.1049/ip-f-1.1984.0114

出版商:IEE    

年代:1984

数据来源: IET

摘要:

An implementation of the principal components transformation is presented which makes use of analogue and digital electronic hardware under the control of a microprocessor. The hardware is used to collect covariance statistics from a multichannel set of digital video images and to perform the actual transformation on real-time analogue video signals derived from the stored data. This approach offers considerable advantages over a completely software based system in terms of speed and cost. An example of the use of the system for the analysis of Landsat multispectral data is presented.

DOI:10.1049/ip-f-1.1984.0115

出版商:IEE    

年代:1984

数据来源: IET