Flow-Based Transmission Scheduling in Constrained Delay Tolerant Networks
Routing is one of the most challenging problems in Delay-Tolerant Networks (DTNs) due to network partitioning and intermittent connectivity. Most existing protocols are based on unlimited bandwidth and buffer size. Previous protocols based on limited bandwidth or buffer size (e.g., MaxProp, RAPID, etc) only consider the scenario that each node has at most one contact opportunity during any time interval, and discuss the packet scheduling mechanisms for each separate contact to minimize the average delivery delay. However, in many applications of DTNs, more than one contact opportunities with the same source node, which are called as related contact opportunities, may arise in the same time interval.