Hi All,

I'm a network engineer looking to better understand the network subsystem of FreeBSD (unix systems) and in particular how it differs from the linux kernel network subsystem. Any good links or books?

I believe iproute2 (this is a package, not a subsystem, right?) is used by linux, so the commands related to it are not available in JUNOS, macOS, and FreeBSD since the sub-system/package in these three kernels is net-tools?

Can someone help me understand this difference - origins and future?
Unix Networking Programming says something like "Linux...networking code and sockets API were developed from scratch." This seems like where the difference started.

Many new networking vendors (e.g. Cumulus and Arista) use linux networking - but I do know OPNsense uses unix.
I wonder if Juniper or Apple ever will switch to the linux network stack - or is there no need to?