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.\"     From:	@(#)lo.4	8.1 (Berkeley) 6/5/93
.\"
.Dd January 10, 2005
.Dt PPP 4
.Os
.Sh NAME
.Nm ppp
.Nd point to point protocol network interface
.Sh SYNOPSIS
.Cd options PPP_BSDCOMP
.Cd options PPP_DEFLATE
.Cd options PPP_FILTER
.Pp
.Cd pseudo-device ppp
.Sh DESCRIPTION
The
.Nm
interface allows serial lines to be used as network interfaces using the
.Em Point-to-Point Protocol
(PPP).
The
.Nm
interface can use various types of compression and has many features
over the SLIP protocol used by the
.Xr sl 4
interface.
.Pp
Supported options are:
.Bl -tag -width 20n -compact
.It Cd options PPP_BSDCOMP
Enable support for BSD-compress (`bsdcomp') compression in ppp.
.It Cd options PPP_DEFLATE
Enable support for deflate compression in ppp.
.It Cd options PPP_FILTER
This option turns on
.Xr pcap 3
based filtering for ppp connections.
This option is used by
.Xr pppd 8
which needs to be compiled with
.Em PPP_FILTER
defined (the current default).
.El
.Sh DIAGNOSTICS
.Bl -diag
.It ppp%d: af%d not supported .
The interface was handed
a message with addresses formatted in an unsuitable address
family; the packet was dropped.
.El
.Sh SEE ALSO
.Xr inet 4 ,
.Xr intro 4 ,
.Xr sl 4 ,
.Xr pppd 8 ,
.Xr pppstats 8
.Rs
.%R RFC 1661
.%D July 1994
.%T "The Point-to-Point Protocol (PPP)"
.Re
.Sh HISTORY
The
.Nm
device appeared in
.Nx 1.0 .
.Sh BUGS
Currently, only the
.Xr ip 4
and
.Xr ip6 4
protocols are supported.