NAME

       ng_sppp — sppp netgraph node type

SYNOPSIS

       #include <netgraph/ng_sppp.h>

DESCRIPTION

       An  sppp  node  is  a netgraph(4) interface to the original sppp(4) network module for synchronous lines.
       Currently, sppp(4) supports PPP and Cisco HDLC protocols.   An  sppp  node  could  be  considered  as  an
       alternative  kernel  mode  PPP  implementation  to  net/mpd  port  +  ng_ppp(4), and as an alternative to
       ng_cisco(4) node.  While having less features than net/mpd + ng_ppp(4), it is significantly easier to use
       in the majority of simple configurations, and allows the administrator to not install the  net/mpd  port.
       With sppp you do not need any other nodes, not even an ng_iface(4) node.  When an sppp node is created, a
       new  interface  appears  which  is  accessible via ifconfig(8).  Network interfaces corresponding to sppp
       nodes are named sppp0, sppp1, etc.  When a node is shut down, the corresponding interface is removed, and
       the interface name becomes available for reuse by future sppp nodes.  New nodes  always  take  the  first
       unused  interface.   The  node itself is assigned the same name as its interface, unless the name already
       exists, in which case the node remains unnamed.  The sppp node allows drivers written to the old  sppp(4)
       interface  to  be  rewritten  using  the newer more powerful netgraph(4) interface, and still behave in a
       compatible manner without supporting both network modules.

       An sppp node has a single hook named downstream.  Usually it is connected directly  to  a  device  driver
       hook.

       The sppp nodes support the Berkeley Packet Filter, bpf(4).

HOOKS

       This node type supports the following hooks:

       downstream  The connection to the synchronous line.

CONTROL MESSAGES

       This node type supports the generic control messages, plus the following:

       NGM_SPPP_GET_IFNAME (getifname)
            Returns the name of the associated interface as a NUL-terminated ASCII string.  Normally this is the
            same as the name of the node.

SHUTDOWN

       This node shuts down upon receipt of a NGM_SHUTDOWN control message.  The associated interface is removed
       and becomes available for use by future sppp nodes.

       Unlike most other node types and like ng_iface(4) does, an sppp node does not go away when all hooks have
       been disconnected; rather, an explicit NGM_SHUTDOWN control message is required.

EXAMPLES

       For example, if you have the cx(4) device, you could run PPP over it with just one command:

             ngctl mkpeer cx0: sppp rawdata downstream

       Now  you have the sppp0 interface (if this was the first sppp node) which can be accessed via ifconfig(8)
       as a normal network interface, or via spppcontrol(8) as an sppp(4) interface.

SEE ALSO

       bpf(4),  cx(4),  netgraph(4),  ng_cisco(4),  ng_iface(4),  ng_ppp(4),  sppp(4),  ifconfig(8),   ngctl(8),
       spppcontrol(8)

       For complex networking topologies you may want to look at net/mpd port.

HISTORY

       The sppp node type was implemented for FreeBSD 5.0.  It was included to the system since FreeBSD 5.3.

AUTHORS

       Copyright (C) 2003-2004 Roman Kurakin <rik@cronyx.ru>

Debian                                          February 3, 2005                                      NG_SPPP(4)