Hwajung Lee’s research while affiliated with George Washington University and other places

We consider the design of survivable logical topologies over physical WDM ring networks. The logical topology consists of the same set of nodes as the physical topology, and the links of the logical topology are lightpaths in the physical topology. The logical topology is said to be survivable if the failure of any single physical link does not disconnect the logical topology. In this paper, we consider the following problem. Given a logical topology with lightpath end-nodes, route the lightpaths to make the logical topology survivable if possible. Otherwise, determine and embed the minimum number of additional lightpaths to achieve survivability.

An important requirement in any high speed network is to ensure the network's survivability, i.e., the ability to provide reroutes of ongoing connections after the failure of network components. We consider the problem of embedding an IP layer topology in the WDM transport network layer with the objective of achieving the network's survivability in the IP layer. Specifically, we consider the problem of embedding an arbitrary IP layer topology in a WDM wavelength-routing ring network such that the IP topology remains connected under the presence of the failure of any link in the WDM layer