Systems and methods are described to enable a so-called ‘unified slice’, wherein the unified slice is technology-independent, i.e., constructed from different networking technologies, and spans multiple operators. The method provides an abstraction of a network slice and its segments, and a way to coordinate the end-to-end slice information collection, slice segment configuration and activation across multiple types of networks and operators. The system of invention has the task of coordinating configuration of an end-to-end slice, with user-specified slice parameters, by communicating with the respective slice managers; It receives information to generate an abstract model of each slice segment, and sends the required slice segment attributes to these slice managers so that they can activate the segment after translating them according to capabilities of their network technology.