245 lines
5.9 KiB
Groff
245 lines
5.9 KiB
Groff
.\" $NetBSD: strip.4,v 1.13 2004/12/05 13:24:10 peter Exp $
|
|
.\"
|
|
.\" Copyright 1996 The Board of Trustees of The Leland Stanford
|
|
.\" Junior University. All Rights Reserved.
|
|
.\"
|
|
.\" Author: Jonathan Stone
|
|
.\"
|
|
.\" Permission to use, copy, modify, and distribute this
|
|
.\" software and its documentation for any purpose and without
|
|
.\" fee is hereby granted, provided that the above copyright
|
|
.\" notice and the above authorship notice appear in all copies.
|
|
.\" Stanford University makes no representations about the suitability
|
|
.\" of this software for any purpose. It is provided "as is" without
|
|
.\" express or implied warranty.
|
|
.Dd December 5, 2004
|
|
.Dt STRIP 4
|
|
.Os
|
|
.Sh NAME
|
|
.Nm strip
|
|
.Nd Metricom Ricochet packet radio wireless network device
|
|
.Sh SYNOPSIS
|
|
.Cd pseudo-device strip
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
driver takes outbound network packets, encapsulates them using the
|
|
.Tn Metricom
|
|
.Qq star mode
|
|
framing, and sends the packets out an
|
|
.Tn RS-232
|
|
interface to a
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radio.
|
|
Packets arriving from the packet radio via the serial link are decapsulated
|
|
and then passed up to the local host's networking stack.
|
|
.Pp
|
|
.Nm
|
|
is an acronym for
|
|
.Sy ST Ns armode
|
|
.Sy R Ns adio
|
|
.Sy IP .
|
|
.Pp
|
|
The
|
|
.Nm
|
|
interfaces can be created by using the
|
|
.Xr ifconfig 8
|
|
.Cm create
|
|
command.
|
|
Each
|
|
.Nm
|
|
interface is a pseudo-device driver for the
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radio, operating in peer-to-peer packet mode.
|
|
.Pp
|
|
In many ways,
|
|
the
|
|
.Nm
|
|
driver is very much like the
|
|
.Xr sl 4
|
|
SLIP pseudo-device driver.
|
|
A
|
|
.Nm
|
|
device is attached to a tty line with
|
|
.Xr slattach 8 .
|
|
Once attached, the interface is configured via
|
|
.Xr ifconfig 8 .
|
|
The major difference between the
|
|
.Xr sl 4
|
|
SLIP pseudo-device driver and the
|
|
.Nm
|
|
driver is that SLIP works only between two hosts over
|
|
a dedicated point-to-point connection.
|
|
.Pp
|
|
In contrast,
|
|
.Nm
|
|
sends packets to a frequency-hopping packet radio, which can address
|
|
packets to any peer
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radio, rather than just to a single host at the other end
|
|
of a point-to-point line.
|
|
Thus, one
|
|
.Nm
|
|
pseudo-device is usually sufficient for any kernel.
|
|
.Pp
|
|
In other respects, a
|
|
.Nm
|
|
interface is rather like an
|
|
.Tn Ethernet
|
|
interface.
|
|
Packets are individually addressed, and subsequent packets can
|
|
be sent independently to different MAC addresses.
|
|
However, the
|
|
.Qq star mode
|
|
framing and MAC addressing are not in any way compatible with
|
|
.Tn Ethernet .
|
|
Broadcast or multicast to more than one packet radio is not possible,
|
|
due to the independent frequency-hopping operation of the packet radios.
|
|
The interface flags
|
|
.Dv IFF_POINTOPOINT
|
|
and
|
|
.Dv IFF_BROADCAST
|
|
are not supported on the
|
|
.Nm
|
|
interface.
|
|
.Pp
|
|
In other words,
|
|
.Nm
|
|
implements a multiple-access, non-broadcast device, accessed via
|
|
an RS-232 serial line, using a proprietary packet framing scheme.
|
|
.Pp
|
|
This version of the
|
|
.Nm
|
|
driver maps
|
|
.Tn IP
|
|
addresses to
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radio addresses using statically configured entries in the
|
|
normal routing table.
|
|
These entries map
|
|
.Tn IP
|
|
addresses of peer packet radios to the MAC-level addresses.
|
|
The exact syntax of this mapping and an example are discussed below.
|
|
The Internet Assigned Numbers Authority
|
|
.Pq Tn IANA
|
|
has allocated an
|
|
.Tn ARP
|
|
type code for use with STRIP.
|
|
A future version of this driver will support
|
|
.Xr arp 4
|
|
to obtain the
|
|
.Tn IP
|
|
address of reachable peer packet radios dynamically.
|
|
.Sh ADDRESS CONFIGURATION
|
|
This version of the STRIP driver requires static pre-configuration of
|
|
the mapping from
|
|
.Tn IP
|
|
addresses to packet radio MAC addresses.
|
|
The
|
|
.Xr route 8
|
|
command should be used to bind a peer STRIP host's packet radio
|
|
.Tn IP
|
|
address to the peer's link-level packet radio address.
|
|
.Pp
|
|
Radio addresses are encoded using the hex equivalent of the packet
|
|
radio's decimal
|
|
.Tn ASCII
|
|
address.
|
|
For example, the following route command will configure a routing
|
|
entry to a packet radio with a MAC address of 1234-5678, and an
|
|
.Tn IP
|
|
address 10.11.12.13, reachable via the
|
|
.Em strip0
|
|
interface:
|
|
.Pp
|
|
.br
|
|
.in 10
|
|
route add -host 10.11.12.13 -link strip0:1:2:3:4:5:6:7:8
|
|
.br
|
|
.in 5
|
|
.Pp
|
|
Generalising from this example to other
|
|
.Tn IP
|
|
addresses and to other 8-digit MAC addresses should be clear.
|
|
.Sh RADIO CONFIGURATION
|
|
The
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radios can auto-baud at speeds up to 38.4K baud.
|
|
At higher speeds -- 57600 or 115200 -- the packet radio cannot autobaud.
|
|
When running at high speeds, the packet radio's serial port should be
|
|
manually configured to permanently run at the desired speed.
|
|
Use a terminal emulator and the Hayes command
|
|
.Ic ATS304=115200
|
|
to set the serial baudrate to the specified number (or 0 for autobaud).
|
|
The command
|
|
.Ic AT\*[Am]W
|
|
will then save the current packet radio state in non-volatile memory.
|
|
.Pp
|
|
.Tn Metricom
|
|
.Em Ricochet
|
|
packet radios can operate in either
|
|
.Dq modem-emulation
|
|
mode or in packet mode (i.e.
|
|
.Qq star mode ) .
|
|
The
|
|
.Nm
|
|
driver automatically detects if the packet radio has fallen out of
|
|
.Qq star mode ,
|
|
and resets it back into
|
|
.Qq star mode ,
|
|
if the baud rate was set correctly by
|
|
.Xr slattach 8 .
|
|
.\" .Sh DIAGNOSTICS
|
|
.Sh SEE ALSO
|
|
.Xr arp 4 ,
|
|
.Xr inet 4 ,
|
|
.Xr sl 4 ,
|
|
.Xr ifconfig 8 ,
|
|
.Xr route 8 ,
|
|
.Xr slattach 8
|
|
.Sh HISTORY
|
|
.Nm
|
|
was originally developed for the
|
|
.Tn Linux
|
|
kernel by Stuart Cheshire of Stanford's Operating Systems and
|
|
Networking group, as part of Mary Baker's MosquitoNet
|
|
.Sy http://mosquitonet.stanford.edu/mosquitonet.html
|
|
project.
|
|
.Pp
|
|
This
|
|
.Nm
|
|
driver was ported to
|
|
.Nx
|
|
by Jonathan Stone at Stanford's Distributed Systems Group and first
|
|
distributed with
|
|
.Nx 1.2 .
|
|
.Sh BUGS
|
|
Currently,
|
|
.Nm
|
|
is IP-only.
|
|
Encapsulations for
|
|
.Tn AppleTalk
|
|
and
|
|
.Tn ARP
|
|
have been defined, but are not yet implemented in this driver.
|
|
.Pp
|
|
.Nm
|
|
has not been widely tested on a variety of lower-level serial drivers.
|
|
.Pp
|
|
The detection and resetting of packet radios that crash out of
|
|
.Qq star mode
|
|
does not always work in this version of the driver.
|
|
One workaround is to kill the
|
|
.Xr slattach 8
|
|
process,
|
|
.Xr ifconfig 8
|
|
the
|
|
.Nm
|
|
interface down, and then start a new slattach and rerun ifconfig
|
|
to enable the interface again.
|