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This paper aims to study the competition problems and market failures in the Canary Islands and propose an alternative management model for the telecommunication transmission network. This model is based on a wholesale-only open-access transmission network, available to all the retail service providers of this region, and managed by a unique entity subject to regulation with cost-based prices. The proposal hopefully will help to debate about the implementation of certain regulatory models in the network industries, concerning telecommunication submarine cables connecting archipelagos.

An empirical approach has been used, based on the observation and analysis of the regulatory policies applied to the wholesale transmission networks in the Canary Islands, Azores and Madeira archipelagos.

Results show a persistent margin squeeze situation on the retail broadband market in the Canary Islands, due to the pricing strategy on the Spanish mainland-Canaries wholesale market, which is, in turn, delaying the entry of alternatives and the level of development and efficiency of competition. The risk of duopoly collusion is also present on this wholesale market. Additionally, public aids will be needed to replace the systems connecting with the non-capital islands and to provide redundancy to El Hierro. The alternative proposal might help preventing the above. Eventually, several insights are considered for further investigation.

Little attention has been paid to this topic in the literature, regarding the analysis of regulatory policies applied over fiber optic submarine cable infrastructures in fragmented territories like archipelagos. Consequently, an empirical analysis has been accomplished to emphasize this research work, based on the regulatory policies adopted.

The purpose of the present study was the development of a methodology for translating predicted rates of decompression sickness (DCS), following tower escape from a sunken submarine, into predicted probability of survival, a more useful statistic for making operational decisions.

Predictions were made, using existing models, for the probabilities of a range of DCS symptoms following submarine tower escape. Subject matter expert estimates of the effect of these symptoms on a submariner’s ability to survive in benign weather conditions on the sea surface until rescued were combined with the likelihoods of the different symptoms occurring using standard probability theory. Plots were generated showing the dependence of predicted probability of survival following escape on the escape depth and the pressure within the stricken submarine.

Current advice on whether to attempt tower escape is based on avoiding rates of DCS above approximately 5%–10%. Consideration of predicted survival rates, based on subject matter expert opinion, suggests that the current advice might be considered as conservative in the distressed submarine scenario, as DCS rates of 10% are not anticipated to markedly affect survival rates.

According to the authors’ knowledge, this study represents the first attempt to quantify the effect of different DCS symptoms on the probability of survival in submarine tower escape.

THE FIRST structurally practicable submarine telegraph cable was manufactured in about 1850, and for the following 100 years the basic submarine cable design remained unchanged. In the 1950's, the development of new submarine cable of armourless design and using modern materials was begun, and this is now in widespread use in new cables. The lack of information on cable performance led to the initiation of a submarine cable recovery programme by the Bell Telephone Laboratories, with the object of investigating the effect of submarine exposure on existing ocean cable materials. Specimens are obtained from cables in service, taken whenever repairs or replacement require that a cable is raised. Since submarine telegraph cables have been in use for over 100 years, the systematic examination of such specimens gives an invaluable source of information on the performance of materials and the effect of environment.