Various MPLS-based IP over WDM integration techniques are considered in this article. In particular, this includes the recent circuit-switching MPλS framework for providing logical IP-layer topologies over optical lightpath routing networks. Additionally, an optical code label switching technique for photonic packet switching and its application to MPLS is also introduced, termed OC-MPLS. The related advantages and challenges of both of these approaches are discussed, and various future research issues are addressed.

This article reports on biologically inspired self-adaptive multi-path routing in overlay networks. Mechanisms found in biological systems are generally robust and adapt well to environmental changes. Therefore, many techniques designed to imitate certain behaviors found in nature have been applied to computer science. Some of these techniques include artificial neural networks, simulated annealing, and genetic algorithms. Certain techniques perform well as optimization techniques for particular problem types.