1. State Key Laboratory of Networking & Switching Technology, Beijing University of Posts & Telecommunications, Beijing 100876, China
2. Beijing Fibrlink Communications Co., Ltd., Beijing 100070, China
3. State Grid Henan Electric Power Company Information and Communication Company, Zhengzhou 450018, China
4. Christian-Albrechts-Universität zu Kiel, Kiel, Schleswig-Holstein 24118, Germany
5. Department of Electrical Engineering, École de Technologie Supérieure ÉTS, Université du Québec, Montreal 8871, Canada