On the gradient-based routing for supporting heterogeneous nodes in Delay Tolerant Networks

基于梯度的路由是时延容忍网络的一种很有前途的方法，它是指每个节点计算一个度量，该度量指示该节点在向目的节点转发消息时可能有多大的用处，并根据该度量来传输消息。传统的基于梯度的路由方法在形成梯度时不考虑节点的移动，这可能会导致消息转发效率低下和性能下降。我们设计了一种基于梯度的路由方法，该方法将节点的移动融入到其梯度中，从而克服了低效的消息转发问题。在节点直行的情况下，使用该方法可以将消息的平均传递延迟降低50%。它的使用还大大减少了最大消息传递延迟。

Gradient-based routing, where each node calculates a metric that indicates how useful the node might be in relaying messages to a destination node and transmits messages according to the metric, is a promising approaches for Delay Tolerant Networks. Conventional gradient-based routing methods do not consider node movement when they form a gradient, which may result in inefficient message relays and degraded performance. We devise a gradient-based routing method that incorporates node movements into its gradient, thereby overcoming the inefficient message relay problem. Use of the proposed method reduces the average message delivery delay by up to 50% w hen the nodes travel straight. Its use also substantially reduces the maximum message delivery delay.