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PPP(4) Device Drivers Manual PPP(4)

ppp —
Point-to-Point Protocol network interface

pseudo-device ppp

The ppp interface allows serial lines to be used as network interfaces using the Point-to-Point Protocol (PPP).

A ppp interface can be created at runtime using the ifconfig pppN create command or by setting up a hostname.if(5) configuration file for netstart(8).

ppp0: afX not supported
The interface was handed a message with addresses formatted in an unsuitable address family; the packet was dropped.

inet(4), pppoe(4), pppx(4), hostname.if(5), ifconfig(8), netstart(8), pppd(8), pppstats(8)

W. Simpson, The Point-to-Point Protocol (PPP), RFC 1661, July 1994.

The ppp device appeared in OpenBSD 1.2.

Currently, only the ip(4) protocol is supported by this device. Note that the pppoe(4) device does support ip6(4).
July 28, 2015 OpenBSD-current