Firstly. the proactive policy to ALM tree which is based on Chord DHT was extended and a back-path scheme with which each node pre-calculates a backup path for itself was proposed. When the non-leaf node leaves. all its child nodes can switch to the respective backup path immediately. https://www.spidertattooz.com/Messerschmitt-Me262A-1A-Fighter-Aircraft-LT-Walter-Hagenah-III-Jagdeschwader-7-Larz-Airfield-Germany-1945-German-Luft/