PPP(8) PPP(8)
NAME
ppp, pptpd - point to point protocol
SYNOPSIS
ip/ppp [ -cCdufSP ][ -b baud ][ -m mtu ][ -p dev ][ -s
username:secret ][ -x netmntpt ][ -t modemcmd ] [ local [
remote ] ]
ip/pptpd [ -d ] [ -p pppnetmtpt ] [ -w window ] [ -D
fraction ] tcp-dir
DESCRIPTION
The Point to Point Protocol is used to encapsulate Internet
Protocol packets for transfer over serial lines or other
protocol connections. Ppp can run either as a client or,
with the -S option, as a server. The only differences
between a client and a server is that the server will not
believe any local address the client tries to supply it and
that the server always initiates the authentication of the
client.
With no option, ppp communicates with the remote system via
standard input and output. This is useful if a program
wants to use ppp in a communications stream. However, the
normal mode is to specify a communications device, usually a
serial line with a modem.
PPP supports the following options:
p communicate over dev instead of standard I/O
u before starting the PPP porotcol with the remote end,
shuttle bytes between the device and standard I/O until
an EOF on standard input. This allows a user to start
ppp and then type commands at a modem before ppp takes
over
b set the baud rate on the communications device
f make PPP add HDLC framing. This is necessary when
using PPP over a serial line or a TCP connection
m set the maximum transfer unit (default 1450)
P use this as the primary IP interface; set the default
route through this interface and write it's configura-
tion to /net/ndb
s supplies the user name and secret to be used in authen-
ticating to the remote side. The username is optional,
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PPP(8) PPP(8)
the default being the local user id. We support both
PPP CHAP and MS CHAP
S run as a server
x use the IP stack mounted at netmntpt
t before starting the PPP protocol, write modemcmd to the
device
c disallow packet compression
C disallow ip header compression
If both the local and remote addresses are specified, don't
ask the other end for either or believe it if it supplies
one. If either is missing, get it from the remote end.
Pptpd is the server side of a PPTP encrypted tunnel. Tcpdir
is the directory of a TCP connection to the client. The TCP
connection is used to control the tunnel while packets are
sent back and forth using PPP inside of GRE packets. The
options are:
d write debugging output to standard error.
p use the IP stack mounted at pppnetmtpt to terminate the
PPP connection.
w set the receive window to window.
D drop fraction of the received packets. This is used
for testing.
SOURCE
/sys/src/cmd/ip/ppp
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