So, you're implying that there is a second person named Alan Cox from Swansea, Wales who worked on FreeBSD, not Linux? Where is your source for that? lol
I do see some networking stuff on there, but much after Apple forked tcp. I don't know that Apple took much memory management from BSD either. Most likely, neither Alan Cox is relevant to Mac.
Alan Cox relevant to Mac is Alan Cox, professor(+etc) at Rice and well known FreeBSD contributor; no connection to Swansea, Wales, AFAIK. https://scholar.google.com/citations?user=z28ApZkAAAAJ&hl=en
I do see some networking stuff on there, but much after Apple forked tcp. I don't know that Apple took much memory management from BSD either. Most likely, neither Alan Cox is relevant to Mac.