Abstract: The invention relates to a method of routing a data packet via a router (12) in a packet communications network (1) supported by a transport network, said method including a step of determining from said packet a required back-up level and a required route. It further includes: a preliminary step of establishing a table storing for a given route links (Ifp1-Ifp6) of the transport network able to provide said route and classified by back-up level; and a step of selecting a link of said transport network in the table on the basis of the required back-up level and the required route.

Abstract: A method of controlling routing in a packet network supported by a transport network allowing the dynamic creation/suppression of links for transporting packets of said packet network, said method including a routing step, a step of informing other routers of said network of the metric assigned to each link of the packet network, and a step of creating/destroying a link. The link may have three states: a non-connected state if said two routers cannot be directly connected, a virtual connection state wherein a virtual metric is assigned to said link between said head end router and said tail end router of the same communication, and a real connection state wherein a real metric is normally assigned to said link.

Abstract: The invention relates to a method of routing a data packet via a router (12) in a packet communications network (1) supported by a transport network, said method including a step of determining from said packet a required back-up level and a required route. It further includes: a preliminary step of establishing a table storing for a given route links (Ifp1-Ifp6) of the transport network able to provide said route and classified by back-up level; and a step of selecting a link of said transport network in the table on the basis of the required back-up level and the required route.

Abstract: The invention relates to a system for protecting a communications network comprising a transport network (3) and end-channel equipment (1) such as routers each connected to said transport network (3) by connecting sections wherein said protective system is provided with first and second protective systems.

Abstract: A method of controlling routing in a packet network supported by a transport network allowing the dynamic creation/suppression of links for transporting packets of said packet network, said method including a routing step, a step of informing other routers of said network of the metric assigned to each link of the packet network, and a step of creating/destroying a link. The link may have three states: a non-connected state if said two routers cannot be directly connected, a virtual connection state wherein a virtual metric is assigned to said link between said head end router and said tail end router of the same communication, and a real connection state wherein a real metric is normally assigned to said link.

Abstract: The invention relates to a system for protecting a communications network comprising a transport network (3) and end-channel equipment (1) such as routers each connected to said transport network (3) by connecting sections wherein said protective system is provided with first and second protective systems.

Abstract: The invention concerns a method of protecting a label switching path in an MPLS network comprising a plurality of nodes connected by IP links, the said path commencing with an ingress node and ending in an egress node of the said network, passing through a given series of nodes and links in the said network, referred to as elements of the said path. When the said ingress node requires the protection of an element of the path, in a first phase a node on the said path, referred to as the PLR point, upstream of the said element to be protected, determines a back-up path, referred to as the bypass tunnel, joining the path upstream of the said element to be protected at a node, referred to as the PM point, and, in a second phase, network resources are reserved on each of the links of the bypass tunnel in order to back up the said path in the event of failure of the said element.

Abstract: Label switching paths in an MPLS network having plural nodes connected by IP links, each path passing through a series of network nodes and links called “elements of the path,” are protected. An element of a first path is protected by a bypass path starting from a node of the first path upstream and ending in a node of the first path downstream of the element to be protected. A certain number of resources of the network are reserved for the bypass path. An element of a second path is protected by a bypass path of the second path starting from a node of the second path upstream of the second element and ending in a node of the second path downstream of the second element. The bypass path of the second path includes at least one part of the resources reserved for the first bypass path.

Abstract: In a system for the regulation of information trains for packet switches, there is provided one queue per path in each input module liable to be driven by an arbitrator placed in each of the output modules bearing these channels.