NAME
ippp —
ISDN synchronous PPP network
driver
SYNOPSIS
pseudo-device ippp count
DESCRIPTION
The
ippp driver interfaces the IP subsystem of the operating
system with the ISDN layer so that a transport of IP packets over an ISDN link
is possible.
For configuration of the
ippp driver, either the
ipppctl(8) utility is used or
it is configured via
isdnd(8) and
its associated
isdnd.rc(5)
file.
In case an IP packet for a remote side arrives in the driver and no connection
is established yet, the driver communicates with the
isdnd(8) daemon to establish a
connection.
The driver has support for interfacing to the
bpf(4) subsystem for using
tcpdump(8) with the
ippp interfaces.
The
ipppctl(8) utility is used to
configure all aspects of PPP required to connect to a remote site.
LINK0 and LINK1
The
link0 and
link1 flags given as
parameters to
ifconfig(8) have
the following meaning for the
ippp devices:
-
-
link0
- Wait passively for connection. The administrative
Open event to the Link Control Protocol (LCP) layer will
be delayed until after the lower layers signal an Up
event (rise of “carrier”). This can be used by lower layers to
support a dial-in connection where the physical layer isn't available
immediately at startup, but only after some external event arrives.
Receipt of a Down event from the lower layer will not
take the interface completely down in this case.
-
-
link1
- Dial-on-demand mode. The administrative
Open event to the LCP layer will be delayed until either
an outbound network packet arrives, or until the lower layer signals an
Up event, indicating an inbound connection. As with
passive mode, receipt of a Down event (loss of carrier)
will not automatically take the interface down, thus it remains available
for further connections.
The
link0 flag is set to
off by default, the
link1 flag to
on.
SEE ALSO
bpf(4),
isdnd.rc(5),
ipppctl(8),
isdnd(8),
tcpdump(8)
AUTHORS
The
ippp device driver was written by
Joerg
Wunsch
<
joerg@freebsd.org>
and then added to ISDN4BSD by
Gary Jennejohn
<
gary@freebsd.org>.
This man page was written by
Hellmuth Michaelis
<
hm@kts.org>.