Performance Assessment of Aggregation and De-Aggregation Algorithms for Vehicular Delay-Tolerant Networks

Vehicular Delay-Tolerant Network (VDTN) is a new opportunistic network approach where vehicles act as the communication infrastructure, furnishing low-cost asynchronous communications, variable delays, and bandwidth limitations. At the edge of the VDTNs, terminal nodes assume the gateway function with other networks, such as the common TPC/IP. In VDTNs, IP packets (datagrams) are aggregated in large data packets, called bundles. At the edge of the network, incoming nodes aggregate datagrams in VDTN bundles and at the destination edge nodes they are de-aggregated in order to retrieve the original IP packets, forwarding them to the upper layers. This paper proposes several aggregation algorithms for VDTNs and studies their performance evaluation through a laboratory testbed. The results show that combination of time and threshold-based algorithms present the best performance and are more suitable for real deployment.