Summary-Vector-Based Effective and Fast Immunization for Epidemic-Based Routing in Opportunistic Networks

In the existing epidemic-based routing algorithms for opportunistic networks, a specific data structure is utilized to store immunity information, which leads to extra control overhead. To address this problem, we propose the following four novel mechanisms: 1) embedding immunity information into summary vectors (SVs), thus no control overhead is required for storing and transmitting immunity information in most cases; 2) improving the SV exchange mechanism; 3) adaptively compressing the size of SVs; and 4) making the neighbors of destinations quickly generate immunity information with a cross-layer method. Theoretical analysis verifies the effectiveness of our proposed mechanisms, and performance evaluation shows that the improved epidemic routing algorithm integrating with the four new mechanisms outperforms the existing epidemic-based routing algorithms in terms of the control overhead and the end-to-end delay of messages.