Both do, as does a large firewall maker (Juniper, I think). They keep certain aspects of the secret sauce back but upstreaming changes is enlightened self-inte

Both do, as does a large firewall maker (Juniper, I think). They keep certain aspects of the secret sauce back but upstreaming changes is enlightened self-interest as they don't have to apply a long series of in-house changes when an upgrade to FreeBSD comes out (Bryan Lunduke had an interview with a FreeBSD maintainer where this was discussed -- I'm not finding that on YouTube though).