Three generations of optic Internet

Professor Mikel Izal from the Public University of Navarre, Basque Country, has analysed the problems to integrate new optic networks in actual network and transfer level (TCP/IP) Internet protocols. This integration will enable to create the core of the second Internet generation in future, the so called Internet 2.

In that area, technological innovations are created everyday and the thesis has been focused on the burst switching networks corresponding to the second optic Internet generation.

Nowadays new optic technologies are based on wavelength division multiplexing. That way, several channels are transferred in a single optic fibre by using different wavelength carriers. Those optic technologies are divided into three generations. The first generation is based on wavelength division multiplexing (WDM). Here it is possible to create high capacity link networks between actual IP routers. The second one offers the possibility to make some operations of direct switching via optic technology. That way, the core of the network may offer optic channels, named Ligthpaths, or it can switch data in large packages, named burst switching networks.

Finally, the third generation would make all steps of channelling and processing of data-packages in the optic level, obtaining a complete optic switching of packages. At the present, the first generation is being implanted, as there are just experimental prototypes or architecture proposals for the second and third generations.

Problems with protocols

One of the theoretical advantage of optic Internet networks would be a faster data-transfer. However, if data is transferred in small packages, even if new networks have more transfer capacity and bandwidth, the network will be slow. In fact, the current problems of transfer time are based on protocols that were designed to have a secure network. Therefore, in order to make better use of speed capacity, data packages must be handled in larger packages.

In order to achieve that result, fractal traffic patterns or autosimilar patterns have been used. In new network architectures, the services of Internet protocols have been analysed, analytic expressions have been obtained and finally, simulations of such networks have been made to estimate the results.

Similarly, to offer the services Internet nowadays has the most effective protocols to be used in the second and third generations have been studied. In those studies the same result has been obtained: actual protocols would reduce significantly the speed in second and third generation networks. Therefore, it would be better to use protocols that have less interaction, but send larger data packages.

Finally, professor Izal has studied Internet traffic in a burst switching system. According to that research, it can be said that Internet and telephone traffic are not the same. The latter is stable in a certain scale, but Internet traffic is more difficult to predict. Therefore, the characteristics of burst traffic have been analysed and, as a consequence, the size and number of bursts have been grouped in a pattern. Indeed, that pattern could be useful for the design of optic switching of core of the network.