ng_rfc1490(4)
NAME
ng_rfc1490 - RFC 1490 netgraph node type
SYNOPSIS
#include <netgraph/ng_rfc1490.h>
DESCRIPTION
- The rfc1490 node type performs protocol encapsulation, de
- encapsulation,
and multiplexing according to RFC 1490 (which has since been - updated by
RFC 2427). This particular type of encapsulation is often - used on top of
frame relay DLCI channels. - The downstream hook is used to transmit and receive encapsu
- lated frames.
On the other side of the node, the inet and ppp hooks are - used to transmit and receive raw IP frames and PPP frames, respectively.
- PPP frames
are transmitted and received according to RFC 1973; in par - ticular, frames
appearing on the ppp hook begin with the PPP protocol num - ber. The
ethernet hook can be used to transmit and receive Ethernet - frames (without a checksum) in RFC 1490's bridging format.
- Typically the inet hook is connected to the inet hook of an
- ng_iface(4)
node.
HOOKS
This node type supports the following hooks:
downstream Connects to the RFC 1490 peer entity.
- ethernet Transmits and receives bridged raw Ethernet
- frames, without
- a checksum.
- inet Transmits and receives raw IP frames.
- ppp Transmits and receives PPP frames.
CONTROL MESSAGES
- This node type supports the generic control messages, plus
- the following:
- NGM_RFC1490_SETENCAP
- This command sets encapsulation method for the node.
- The desired
method must be passed as a string message argument, - and must be
one of the following supported encapsulation modes: - "ietf-ip" IP packets are sent using simple
- RFC1490/2427
encapsulation.
- "ietf-snap" IP packets are sent inside SNAP
- frames. Also
- conforms to RFC1490/2427.
- "cisco" IP packets are sent and received
- using propri
- etary Cisco encapsulation method.
- NGM_RFC1490_GETENCAP
- This command returns current encapsulation method on
- the node.
SHUTDOWN
- This node shuts down upon receipt of a NGM_SHUTDOWN control
- message, or
when all hooks have been disconnected.
SEE ALSO
netgraph(4), ng_frame_relay(4), ng_iface(4), ngctl(8)
- C. Brown and A. Malis, Multiprotocol Interconnect over Frame
- Relay, RFC
2427. - W. Simpson, PPP in Frame Relay, RFC 1973.
- http://www.cisco.com/warp/public/121/frf8modes.pdf
HISTORY
The ng_rfc1490 node type was implemented in FreeBSD 4.0.
AUTHORS
Julian Elischer <julian@FreeBSD.org>
BUGS
- Not all of RFC 1490 is implemented.
- BSD January 19, 1999