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 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.
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_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.
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.