SR‐SAAD: A Social Rank‐Based Routing Protocol for Enhanced Efficiency in Delay Tolerant Networks
Saif Ullah, Asif Muhammad, Zulfiqar Ali, Muhammad Waqar, Ajung Kim · IET Communications · 2025
ABSTRACT Traditional networks face challenges in delivering messages when no direct path exists between the nodes. Delay tolerant networks (DTNs) address this issue through specialised algorithms, many of which leverage social metrics to select optimal relay nodes. While these approaches improve message delivery, they often incur high overhead costs. This paper introduces the SR‐SAAD routing protocol for DTNs, which aims to balance efficiency and performance by using three social metrics: degree centrality, social activeness, and random walk encounter (RWE). The philosophy behind SR‐SAAD is to prioritise nodes that exhibit higher social connectivity and activity, ensuring that messages are forwarded through nodes with the best potential to enhance delivery performance while minimising the overhead associated with more traditional methods. According to the proposed routing strategy, each node in the network first calculates its degree centrality, social activeness, and RWE. These values are then aggregated to compute a social rank (SR) for each node, which is shared with neighbouring nodes. Nodes that meet specific criteria—having a higher SR and exceeding a threshold—are shortlisted as potential relay nodes. The message is forwarded to the node with the highest SR value, and this process continues until the message reaches its destination. The design philosophy behind this approach is to use social metrics that correlate with real‐world human behaviours, optimising the selection of relay nodes for efficient data forwarding. We run simulations for 12 h using different buffer sizes. Simulation results show that SR‐SAAD outperforms traditional approaches such as Epidemic, PRoPHET, PRoPHETv2, and first contact, improving the packet delivery ratio (PDR) by delivering 936 messages out of 1440 messages about 533 (936–403) more messages than epidemic with the same set of parameter values, with fewer hops and reduced overhead, albeit at the expense of increased average latency.