Simulation-based performance evaluation of resource allocation algorithms for implementation in the SHF-DAMA satellite network

Sponsored by DISA, the SHF-DAMA standard addresses the warfighter's requirements for flexible, reliable, and efficient (technically and fiscally) satellite communications. The standard proposes a system supporting both packet data transfer and single-channel-per-carrier voice and data circuits assigned on a demand basis. The standard does not address management of the DSCS III transponder's bandwidth and power resources among priority classes of users. This paper summarizes an effort to characterize the SHF-DAMA system's performance over each combination of the following resource management algorithm features: preemption enabled and disabled; using the standard-specified collision resolution technique and a binary exponential backoff; and using complete partitioning, complete sharing, and sharing with minimum allocation strategies. The authors introduce a novel algorithm for avoiding unnecessary preemption. A simulation written in MODSIM II collects the following measures of performance over a broad load range: call establishment delay, number of calls simultaneously supported, power used, and number of calls preempted. The primary conclusion drawn using graphical and hypothesis testing methods is that the SHF-DAMA system should implement the complete sharing management algorithm. This algorithm reduces the call setup time and most efficiently manages the satellite's resources. As a secondary conclusion, the binary exponential backoff retransmission strategy does not provide significantly better performance than the standard-specified backoff.