**5. Conclusions**

Optical burst switching is seen as a candidate technology for next-generation transport networks. This chapter has described and analyzed the performance benefits of a strategy to enforce traffic engineering in the wavelength domain in OBS networks. The TE-DBS strategy is based on using the HMPI algorithm to optimize offline the order by which wavelength channels are searched for each routing path and employing at the ingress nodes a selective delaying of data bursts as a way to maximize the amount of burst traffic sent via the wavelength channels ranked with highest priority. Both the HMPI offline algorithm and the online selective delaying of bursts were revisited and exemplified.

A network simulation study has highlighted the performance improvements attained by using TE-DBS in an OBS network with dedicated full-range wavelength converters and with shared full-range wavelength converters. It was shown that the utilization of the TE-DBS strategy enables to reduce the average burst blocking probability for a given average offered traffic load, or augment the average offered traffic load for an objective burst blocking probability, when compared to utilizing a known contention minimization strategy. The simulation results shown that increasing the maximum delay a burst can experience at the ingress node and augmenting the number of wavelength channels per link can improve the effectiveness of the TE-DBS strategy and also provided evidence of the burst serialization and traffic isolation in different wavelengths inherent to this strategy. Finally, the analysis confirms that the utilization of TE-DBS in OBS networks with shared full-range wavelength converters can provide noticeable savings in the number of expensive all-optical wavelength converters and a smaller increase in the size of the switch matrix of the core nodes.
