If you decide that you wish to use Mark Salyzyn's Mux serial driver instead of the standard NeXT serial drivers, then see: ftp://next-ftp.peak.org/pub/next/drivers/misc/ for the latest version. The Mux serial driver usually provides better (and more stable) performance than the standard serial drivers. It is not required for PPP operation, but it is recommended. Also, if you do use Mux, make sure you use a version of PPP that is at least as current as: ppp-2.3.5-0.5.2bpl1