Investigation of least resistance routing in a mobile SINCGARS packet radio network

Given the mobility requirements, the need for multihop (i.e., store-and-forward) operation, and the variability of the link conditions, distributed network protocols are necessary in order to make a reliable network out of the collection of unreliable links. Mobile, multiple-hop packet radio networks must route packets through several radios in order to deliver packets to their destinations. Least resistance routing (LRR) is specifically designed for routing packets in a tactical packet radio network. A unique feature of LRR is that it incorporates side information into the routing protocol for the purpose of detecting the presence of interference. The routing tables are adjusted to avoid particular radios and regions of the network that are subjected to high levels of partial-band or multiple-access interference. A simulation of a frequency hopping packet radio network using the SINCGARS radio is utilized to examine the performance of LRR in a realistic tactical environment. The model of the SINCGARS radio allows for greater detail in accounting for mobile partial-band jamming and FH multiple-access interference than has been possible in previous investigations. Both link and transport layer acknowledgments along with retransmission of dropped packets are modeled. The performance of LRR is compared to a conventional shortest path routing algorithm. LRR algorithms using both node and link resistance measures are investigated as well as a number of different routing metrics. Networks with both static and mobile user topologies are simulated.