Abstract
This paper addresses critical improvements in the Schedule-Aware Bundle Routing (SABR) standard, pivotal for distributed space missions based on Delay-Tolerant Networking (DTN). With a focus on volume management, defined as efficiently allocating and utilizing the data transmission capacity of network contacts, we explore enhancements for distributed and scheduled DTNs. Our analysis begins by identifying and scrutinizing existing gaps in volume management within the SABR framework. We then introduce a novel concept coined \textit{contact segmentation}, which streamlines the management of the transmission volumes. Our approach spans all network contacts, initial and subsequent, by unifying previously separate methods such as Effective Volume Limit (EVL), Earliest Transmission Opportunity (ETO), and Queue-Delay (QD) into a single process. Lastly, we propose a refined generic interface for volume management in SABR, enhancing the system’s maintainability and flexibility. These advancements rectify current limitations in volume management and lay a foundation for more resilient and adaptable space DTN operations in the future.