ng_rfc1490 —
RFC
1490 netgraph node type
#include
<netgraph/ng_rfc1490.h>
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 encapsulated 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 particular, frames appearing on the
ppp hook begin with the PPP protocol
number. 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.
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.
This node type supports the generic control messages, plus the following:
-
NGM_RFC1490_SET_ENCAP
(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 proprietary
Cisco encapsulation method.
-
NGM_RFC1490_GET_ENCAP
(getencap)
- This command returns current encapsulation method on the
node.
This node shuts down upon receipt of a
NGM_SHUTDOWN control message, or when all
hooks have been disconnected.
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
The
ng_rfc1490 node type was implemented in
FreeBSD 4.0.
Julian Elischer
<
[email protected]>
Not all of RFC 1490 is implemented.