Dynamic hitless resizing in optical transport networks

Abstract

The invention relates to techniques for controlling a dynamic hitless resizing in data transport networks. According to a method aspect of the invention, a network connection comprises M tributary slots defined in a payload area of a higher order transport scheme of the data transport network and the method comprises the steps of receiving a connection resize control signal at each of the nodes along the path of the network connection; adding at each node along the path in response to the connection resize control signal a second set of N tributary slots to the first set of the M tributary slots, such that the network connection comprises M+N tributary slots; and increasing, after M+N tributary slots are available for the network connection at each node along the path, a transport data rate of the network connection.

What is claimed is: 
     
         1 . A method for controlling dynamic hitless resizing of an Optical Data Unit flex (ODUflex) network connection in a data transport network, when the ODUflex network connection is to be incremented, the method comprising:
 receiving, by an ingress end node, a connection resize control signal CTRL ADD;   adding a set of N tributary slots to a set of M tributary slots; and   increasing, a bandwidth of the signal passing through the network connection, after M+N tributary slots are available for the ODUflex network connection at each node along a path in a manner synchronized with a downstream node by passing a tributary slot connectivity check (TSCC) signal;   wherein the path of the ODUflex network connection extends between two connection end nodes, or extends over one or more intermediate nodes of the data transport network;   wherein the ODUflex network connection transports data of client services in transport frames from the ingress end node to an egress end node; and   wherein the ODUflex network connection comprises the set of the M tributary slots defined in a payload area of a higher order transport scheme of the data transport network.