CMCC, Inc. CMCC, Inc. CMCC, Inc. Tsinghua University Tsinghua University Tsinghua University This document describes a mechanism of providing mapping service for LISP-like architecture. The mapping service comprises of EID Router (ER) mechanism and supplementary DHT Mapping Overlay (MO), in which ER mechanism is for reducing forwarding entries in routers while driving the packets to the destination through tunnels, and the DHT MO serves as a supplement that provides specific mappings to reduce the number of tunnels. The mechanism is flexibly deployable for ISPs since it costs little and is easy to progress.