Abstract: The present invention relates to a method for protecting an optical telecommunication network against possible failures and signal degrades, the network comprising at least two nodes; working resources and protecting resources connecting the nodes; a first protection mechanism operating at a first protection layer; and a second protection mechanism operating at a second protection layer, characterized by a) the step, carried out by a node detecting a failure that could be managed by said first mechanism, of sending downstream an in-band Forward Protection Indication signalling in order to instruct the second protection mechanism not to operate, or b) the step, carried out by a node detecting a Bit Error Rate between a certain range, of sending downstream an in-band Link Degradation Indication signalling in order to instruct the second protection mechanism to operate.

Abstract: The present invention provides for a method and apparatus for using the complete resource capacity of a synchronous digital hierarchy infrastructure, with a protection system, in the presence of a data (packet) network, in which the complete SDH/SONET protection (spare) capacity is used to carry data traffic in both normal and failure conditions. In case of failure the working capacity is cut, and the TDM traffic is subject to a protection mechanism and is shifted over the protection capacity; the part of high (and medium) priority data traffic is shifted over the protection capacity; a part of the data low-priority extra-traffic (transported over the protection capacity in normal conditions) will share the remaining protection capacity with the low-priority best-effort part of the data traffic transported over the working capacity.

Abstract: A SONET/SDH frame providing for an optimized management of K1 and K2 bytes of protection protocol and providing for the management of a number of nodes higher than sixteen, which is the highest number which is provided for at the present time. In practice, the bits of a third byte (K0) of Multiplex Section OverHead are used in such a way that at least one of them represents a Source Node IDentification Extension bit, at least one of them represents a Destination Node IDentification Extension bit and at least one bit of those remaining indicates a change of the information in said first, second or third bytes (K1, K2, K0). In this way, the nodes which can be managed can be even 128 and the switching rate could be highly increased.

Abstract: The present invention relates to a method for protecting an optical telecommunication network against possible failures and signal degrades, the network comprising at least two nodes; working resources and protecting resources connecting the nodes; a first protection mechanism operating at a first protection layer; and a second protection mechanism operating at a second protection layer, characterized by a) the step, carried out by a node detecting a failure that could be managed by said first mechanism, of sending downstream an in-band Forward Protection Indication signalling in order to instruct the second protection mechanism not to operate, or b) the step, carried out by a node detecting a Bit Error Rate between a certain range, of sending downstream an in-band Link Degradation Indication signalling in order to instruct the second protection mechanism to operate.

Abstract: The present invention provides for a method and apparatus for using the complete resource capacity of a synchronous digital hierarchy infrastructure, with a protection system, in the presence of a data (packet) network, in which the complete SDH/SONET protection (spare) capacity is used to carry data traffic in both normal and failure conditions.

Abstract: The present invention provides for a method and apparatus for shared protection in an Optical Transport Network ring based on the ODU management, based on the access of the APS/PCC bytes of the ODU Overhead at nodes, preferably by a dedicated sub-layer (like the Tandem Connection Monitoring TCM), and on the use of an end-to-end signaling APS protocol in an ODU-Shared Protection Ring topology.