Comparing Performance of IPv6 multicast and unicast for software updates F4Fp-SME-COD210601-05 All software has bugs. All connected devices require software updates to be secure – everything from the largest server infrastructure to the smallest IoT device. The network component of a software update is a data transfer. A file or files need to be distributed from a central point to potentially billions of nodes. Presently, in almost all cases, these updates are delivered via unicast. By devices, we do not just mean IoT but the entire infrastructure internet. Routers, VOIP, mobile phones, consumer devices. A device that is connected to a network will at some point require updates. The experiment aimed to show a marked improvement over unicast for this use case so that the application of multicast for other (non-streaming) will become clear. Librecast aimed to show the fundamental difference in thinking between unicast and multicast. Specifically, in comparison to unicast, multicast; uses less bandwidth requires less infrastructure has a lower power consumption has a lower carbon footprint can lower financial costs, both capital and operating costs can make better use of on-demand (cloud) infrastructure has privacy improvements over unicast The network component of a software update is a data transfer. A file or files need to be distributed from a central point to potentially billions of nodes. Presently, in almost all cases, these updates are delivered via unicast. By devices, we do not just mean IoT but the entire infrastructure of the internet. Routers, VOIP, mobile phones, consumer devices. Everything that is connected to a network will need updates. If we can show a marked improvement over unicast for this simple and universal use case, utilization of multicast for other (non-streaming) cases becomes much clearer. Librecast aims to show the fundamental difference in thinking between unicast and multicast. Release for archival on Zenodo along with: Report: https://doi.org/10.5281/zenodo.6470929 Data : https://doi.org/10.5281/zenodo.6382741