A joint “packet-optical” layer restoration mechanism protects against single, packet-layer router failures by managing network resources from both the packet layer and the optical transport layer in a synergistic manner. It reuses packet-layer router service-ports and/or transport-layer service wavelengths...http://www.google.de/patents/US20050063299?utm_source=gb-gplus-sharePatent US20050063299 - Joint-layer restoration in packet-over-optical networks
