node type performs encapsulation and de-encapsulation of packets
using the Cisco HDLC protocol.
This is a fairly simple
protocol for the transmission of packets across
high speed synchronous lines.
Each packet is prepended with
an Ethertype, indicating the protocol.
There is also a
hook should connect to the synchronous line.
On the other side
of the node are the
hooks, which transmit and receive raw IP, IPv6, AppleTalk, and IPX packets,
Typically these hooks would connect to the corresponding
hooks on an
In order to function properly for IP traffic, the node must be informed
of the local IP address and netmask setting.
This is because the protocol
packet which we must be prepared to answer.
There are two ways to accomplish this, manually and automatically.
Whenever such an inquire packet is received, the node sends a
control message to the peer node connected to the
hook (if any).
If the peer responds, then that response is used.
This is the automatic method.
If the peer does not respond, the node falls back on its cached value
for the IP address and netmask.
This cached value can be set at any time
message, and this is the manual method.
hook is connected to the
hook of an
node, as is usually the case, then configuration is automatic as the
This node type supports the following hooks:
The connection to the synchronous line.
This node type supports the generic control messages, plus the following:
This command takes an array of two
The first is the IP address of the corresponding interface
and the second is the netmask.
This command returns the IP configuration in the same format used by
This command is also
by this node type to the
peer whenever an IP address inquiry packet is received.