1. A method for forwarding a service in a data communication device, comprising: constituting a fast forwarding table, FIB, in the data communication device, the FIB comprising a Route Prefix, and a pointer pointing to a Next Hop Array corresponding to the Route Prefix; wherein the pointer comprises a flag bit adapted to determine whether to add a private domain to the Route Prefix according to a value of the flag bit; wherein the private domain is adapted to save the private data of the Route Prefix; if it is determined to add the private domain to the Route Prefix according to a value of the flag bit, querying, by a data plane of the data communication device, the private data of each Route Prefix and the Next Hop Array corresponding to the Route Prefix from the FIB, and forwarding a data packet in the data communication device according to a query result.