Density-Aware Delay-Tolerant Interest Forwarding in Vehicular Named Data Networking

Named Data Networking (NDN) has been considered as a promising networking architecture for Vehicular Ad-Hoc Networks (VANETs). However, Interest forwarding in NDN suffers severe issues in vehicular environment. Broadcast storm results in much packet loss and huge transmission overhead. Also, link disconnection caused by highly dynamic topology leads to low packet delivery ratio. On the other hand, traffic data are playing significant roles in VANETs since they are essential in varieties of Intelligent Transportation System (ITS) applications. Thus, an efficient NDN forwarding strategy using geographical characteristics to retrieve traffic data is urgently required. In this paper, we propose Density-Aware Delay-Tolerant (DADT) Interest forwarding strategy to retrieve traffic data in vehicular NDN with the purpose of improving packet delivery ratio. DADT specifically addresses data retrieval during network disruptions using Delay Tolerant Networking (DTN). It makes retransmission decision based on directional network density. Also, DADT mitigates broadcast storm by using rebroadcast deferring timer. We compared DADT against other strategies through simulation and the results show that it can achieve higher satisfaction ratio while keeping low transmission overhead.