OSPF Configurable SRGB

A segment is encoded as an MPLS label. An ordered list of segments is encoded as a stack of labels. Every node in the segment routing domain is allocated labels by the node label manager based on the index range configured for source packet routing. These labels are allocated to the node segment based on the availability of the dynamic label range managed by node label manager. A segment routing global block (SRGB) is the range of label values used in segment routing. This feature introduces an option to configure an available SRGB label range for the OSPF protocol so that the labels are predictable across segment routing domains. Ensure that the configured SRGB labels are not used by any other application.