China Mobile China Mobile New H3C Technologies New H3C Technologies Huawei Technologies ZTE Corporation Ruijie Networks Co., Ltd. This document describes a Segment Routing based solution for two- level hierarchical IETF network slices. Level-1 network slice is realized by associating Flex-Algo with dedicated sub-interfaces, and level-2 network slice is realized by using SR Policy with additional NRP-ID on data plane.