Performance Assessment of Caching and Forwarding Algorithms for Vehicular Delay Tolerant Networks

Vehicular delay tolerant networks (VDTNs) were proposed as a novel disruptive network concept based on the delay tolerant networking (DTN) paradigm. VDTN network architecture uses vehicles to relay messages, enabling network connectivity in challenged scenarios. Due to intermittent connectivity, network nodes carry messages in their buffers, relaying them only when a proper contact opportunity occurs. The storage capacity and message retrieving of intermediate nodes directly affects the network performance. Therefore, efficient and robust caching and forwarding mechanisms are needed. This paper proposes a content storage and retrieval solution for VDTN networks. It consists on storage and retrieval control labels, attached to every message of aggregated traffic (data bundles). These labels define cacheable contents, and apply cache-control and forwarding restrictions on data bundles. This solution is fully automated, providing a fast, safe, and reliable data transfer and storage management, while improves the applicability and performance of VDTN networks significantly. The proposed algorithms were evaluated and validated through a VDTN testbed.