An Efficient Control Method of Multi-copy Routing in DTN

Delay/Disruption Tolerant Networks (DTN) often use multi-copy routing protocols to improve the efficiency that the messages are delivered successfully, but the network load is increased by vast message copies. A new scheme is presented using threshold method on multi-copy routing protocol. The all nodes are added an encounter counter in the message transferred. If the counter reaches the set threshold of counter, the node removes the message copy. With the proper threshold, the message copies decrease obviously and are removed completely in the end, at the same time the successful delivery efficiency is still the same as the Epidemic Routing. In some environments we can abandon TTL or anti-packet approach about redundancy removing of message copies. In simulation, we compare variation trend of the message copies among vary threshold in two scenes.