A Routing Scheme for Bulk Data Transfers in Multi-Domain OCS Networks with Assistive Storage.

Rapid growth of traffic leads to bottlenecks on inter-domain links, and the residual bandwidth on such links exhibits temporal and spatial variations. There may not be sufficient bandwidth for end-to-end cross domain transmission upon the arrival of bulk data requests. Storage can be introduced into the forwarding path so that the delay tolerant data can be temporarily stored and forwarded when network links become less congested. In this paper, we study the Store-and-Forward (SnF) problem in a multi-domain environment. We present a routing scheme based on a framework named TS-MLG (time-shifted multilayer graph) to perform inter-domain bulk data transfer by taking both spatial and temporal aspects into consideration. With this scheme, the cross-domain routing path, as well as the storage points and the time of transmission, can be determined through conventional routing computations. An updating strategy is proposed to realize temporal bandwidth information exchange between physical and logical layers. Numerical simulations reveal that SnF can improve the inter-domain bandwidth utilization and optimize the network performance at the practical cost of network states maintenance overhead and computational complexity. Since the multi-domain routing is sensitive to the burden of the control plane, we also studied factors that affect computational complexity.