Abstract: When a failure occurs on a path set between two packet communication devices, a protection path is set and the communication is recovered without having the effect of the path failure on devices other than the two packet communication devices.

Abstract: In a communication system, including a plurality of communication node apparatuses, for establishing a path for communication by exchanging a message among the plurality of communication node apparatuses, before establishing a path, an identifier of a path for which reuse of resources of the path to be established is permitted or inhibited is determined, and the determined identification information is included in a control message so that the path is established. A communication node apparatus in which the path has been established determines availability of reuse of resources the path based on the identification information in the control message. When an event such as failure occurrence, occurrence of resource reuse or dissolution of resource reuse occurs, the communication node apparatus executes path priority change processing, so that priority can be changed such that resource reuse can be performed most efficiently.

Abstract: In a communication system, including a plurality of communication node apparatuses, for establishing a path for communication by exchanging a message among the plurality of communication node apparatuses, before establishing a path, an identifier of a path for which reuse of resources of the path to be established is permitted or inhibited is determined, and the determined identification information is included in a control message so that the path is established. A communication node apparatus in which the path has been established determines availability of reuse of resources the path based on the identification information in the control message. When an event such as failure occurrence, occurrence of resource reuse or dissolution of resource reuse occurs, the communication node apparatus executes path priority change processing, so that priority can be changed such that resource reuse can be performed most efficiently.

Abstract: When a failure occurs on a path set between two packet communication devices, a protection path is set and the communication is recovered without having the effect of the path failure on devices other than the two packet communication devices.

Abstract: A multi-layer photonic network and nodes used therein are provided. The multi-layer photonic network comprises a packet network which performs switching and transfer in packet units, and a photonic network comprising optical transmission lines and photonic switches, and which accommodates the packet network. The multi-layer photonic network also has a two layer structure of optical wavelength links (O-LSPs) and packet links (E-LSPs). The O-LSPs are constituted by the optical transmission lines and comprise optical wavelength switching capability (LSC) which is capable of switching in optical wavelength units and packet switching capability (PSC) which is capable of switching in packet units at both their ends. The E-LSPs include the O-LSPs and PSCs at both their ends. Each node includes a section for automatically establishing an O-LSP according to an establishment request for an E-LSP while taking account of path information including path cost, resource consumption, and traffic quantity.

Abstract: A wavelength division multiplexing ring network is constructed using a simple architecture and a fewer number of hardwares between the nodes compared with the conventional ring network. Each node is structured so that any number of multiple waves can be processed, and a fault in the network or within a node is resolved by providing a path-based protection so that switching can be performed without disrupting other nodes or even within one node.

Abstract: A multi-layer photonic network and nodes used therein are provided. The multi-layer photonic network comprises a packet network which performs switching and transfer in packet units, and a photonic network comprising optical transmission lines and photonic switches, and which accommodates the packet network. The multi-layer photonic network also has a two layer structure of optical wavelength links (O-LSPs) and packet links (E-LSPs). The O-LSPs are constituted by the optical transmission lines and comprise optical wavelength switching capability (LSC) which is capable of switching in optical wavelength units and packet switching capability (PSC) which is capable of switching in packet units at both their ends. The E-LSPs include the O-LSPs and PSCs at both their ends. Each node includes a section for automatically establishing an O-LSP according to an establishment request for an E-LSP while taking account of path information including path cost, resource consumption, and traffic quantity.