[Differential] D25681: if_spppsubr: Define a few LCP options, Recognize (but still reject) multilink PPP config options

[Eugene Grosbein]

16.07.2020 14:12, lutz_donnerhacke.de (Lutz Donnerhacke) wrote:

>   > ce(4) for PCI G.703/E1 card,
>   > cp(4) for PCI V.35/RS-232/RS-530/RS-449/X.21/G.703/E1/E3/T3/STS-1 cards,
>   > and cx(4)/ctau(4) for some ISA cards but these do not exist in FreeBSD 13 anymore,
>   > removed by emaste@ recently.
>   >
>   > Both ce(4) and cp(4) are i386-only drivers at present.
>   
>   Such synchronous lines are still in use (here):
>   
>   - G.703 is common in phone systems.
>   - X.21 for leased lines (with old contracts),
>   - E1/E3 for SDH (carrier grade) leases lines.
>   - RS-232 is the ordinary serial port, the other RS- are industry specific serials (mainly other voltages)

This is not about lines and protocols, this is about old PCI cards for PCs manufactured 15+ years ago.

>   But you are right: Do we really need a specialized PPP hardware support these days?
>   Do we really want to run a recent kernel on this antique hardware? It would be a sacrilege.
>   
>   Normal PPP over serial lines (currently available) does work using ppp(4)