A method includes obtaining, by a management device, sub-interface information that includes a correspondence between an identifier of a first sub-interface of a first device and a first network slice identifier, a correspondence between an identifier of a second sub-interface of a second device and a second network slice identifier, and information indicating that the first sub-interface is directly connected to the second sub-interface, and determining, by the management device, a network slice topology based on the obtained sub-interface information.