1.\" $NetBSD: sl.4,v 1.1 1996/08/10 21:26:14 explorer Exp $ 2.\" 3.\" Copyright (c) 1983, 1991, 1993 4.\" The Regents of the University of California. All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" From: @(#)lo.4 8.1 (Berkeley) 6/5/93 31.\" $FreeBSD: src/share/man/man4/sl.4,v 1.8.2.1 2000/12/08 14:59:08 ru Exp $ 32.\" $DragonFly: src/share/man/man4/sl.4,v 1.2 2003/06/17 04:36:59 dillon Exp $ 33.\" 34.Dd August 10, 1996 35.Dt SL 4 36.Os 37.Sh NAME 38.Nm sl 39.Nd slip network interface 40.Sh SYNOPSIS 41.Cd "pseudo-device sl" Op Ar count 42.Sh DESCRIPTION 43The 44.Nm 45interface allows serial lines to be used as network interfaces using the 46.Em slip 47protocol. The 48.Nm 49interface can use Van Jacobson TCP header compression and ICMP filtering. 50This is arranged by using the various link-level flags to the 51.Xr ifconfig 8 52command: 53.Pp 54.Bl -tag -width LINK0X -compact 55.It Em link0 56Enable VJ header compression. 57.It Em link1 58Suppress ICMP traffic. 59.It Em link2 60Enable VJ header compression autodetection. This will turn on the 61.Em link0 62flag as soon as the first VJ-compressed packet has been seen by 63the driver. 64.El 65.Sh DIAGNOSTICS 66.Bl -diag 67.It sl%d: af%d not supported. 68The interface was handed 69a message with addresses formatted in an unsuitable address 70family; the packet was dropped. 71.El 72.Sh SEE ALSO 73.Xr inet 4 , 74.Xr intro 4 , 75.Xr slattach 8 , 76.Xr sliplogin 8 , 77.Xr slstat 8 78