在傳統的DTN路由協定中，由於網路拓樸的快速變動，為了能將訊息封包傳送到目的地，通常是透過大量的複製，或是透過資訊的過濾與計算，將封包交由適合的節點來協助傳送。
然而在電池電源有限的條件之下，過於冗餘的封包複製傳遞，或CPU運算的大量使用，將使得節點容易因電量耗盡而失去傳遞的功能，不只是造成整體系統的存活時間(System Lifetime)降低，亦非常不利於維持整體網路的傳遞成功率(Delivery Ratio)。
在旅行的過程中，同行的人們通常具有相同的移動軌跡以及最終目的地，因而形成團體行動的模式；針對這樣的特性，我們採用每個團隊只留下一位領隊來統籌探索鄰居及封包傳遞的概念，透過GPS的資訊輔助來設計出組隊省電機制，延長節點存活時間，進而提升系統存活時間，並在運算複雜度較低且封包冗餘複製亦降低的狀況下，仍保有不錯的傳遞成功率以及較低的效能衰減。

In traditional routing protocols of DTNs, most of them are using redundancy messages and information computing to make a good relay decision.
Due to energy limitation, too many redundant message transmissions or high computing will make nodes die off quickly. It will decrease the system lifetime and diminish the delivery ratio of the whole system.
When people go on a tour, friends always form a group due that members have a similar moving path and destination. Based on the features of moving patterns, we design a grouping scheme, namely, Energy-aware Grouping, with the concept that there is only one node awake in a group in charge of contact and message transmissions. With the assistance by GPS, our method has reduced the numbers of redundant message transmissions and information computing. Simulation results show that it can extend the system lifetime with maintaining still good delivery ratio

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