Useful description from the documentation about what is new about this as amateur packet radio has a long history.

The NPR protocol is designed to transfer IP data over radio links, in a bidirectional way (single frequency). This protocol is in the middle between old packet radio (AX.25) and HSMM-Hamnet with Wifi equipment. This protocol is designed by a HAM for HAMs. The project is 100% open source : specification, software, PCB.

This solution is complementary to HSMM-Hamnet (which uses Wifi equipments), on lower frequencies 70cm). Radio links on 70cm band is much more robust to obstacles. The data-rate available is also much smaller, but yet useable. We can achieve several hundreds of kbps. The protocol is designed for “point to multipoint” topology, with 1 central relay (called Master) and several clients around.