The Point to Point Protocol is used to encapsulate Internet Protocol packets
for transfer over serial lines or other protocol connections.
Pppclient
makes a connection to a PPP server and
passes IP packets over the connection.
If
dialdevice
is omitted, standard input and output are used as the connection.
If
dialdevice
begins with a
slash,
pppclient
assumes it is a file name,
open(2)'s
it, and uses the result as the connection.
Otherwise,
dialdevice
is passed as the
destination address to
dial(2)
to set up the connection.
If the connection is successful,
pppclient
creates a pipe, pushes the IP line discipline onto it, and sets the
local and remote addresses of the IP interface to
myipaddr
and
peeripaddr.
It then loops transferring packets between the pipe and the connection.
If either
myipaddr
or
peeripaddr
is omitted,
pppclient
requests them from the server.
The options are
d
print debugging information.
b
baud rate of the serial line.
p
peer ip address (in case the peer asks for its ip address over IPCP).
i
the local ip address to be established for this connection.
Pppserver
treats serial lines as PPP connections, switching packets between
them and the local machine.
It creates a pipe for a local IP interface (address
myipaddr),
opens a set of serial lines,
and switches packets between the local interface
and the serial lines.
Ndev
specifies the number of serial devices to serve.
The devices are named
/dev/eia{firstdev}
through
/dev/eia{firstdev+ndev-1}
Their remote IP addresses are
firstipaddr
through
firstipaddr+ndev-1.
The default baud rate is 9600.
If any arguments follow
firstdev
(baud0,
baud1,
...), they are used as baud rates for the serial lines.
The only option,
-d,
turns on debugging output.
Both
pppclient
and
pppserver
accept all options defined in RFCs 1331 and 1332.
EXAMPLES
Start up a server for serial lines
/dev/eia[2-6]
with remote IP addresses 131.107.1.100 through
131.107.1.103 and baud rates of
19200, 2400, 9600, 9600.
The local IP address is 131.107.1.1.