Packet Layer to Device Driver
-----------------------------
-First Byte = 0x00
+First Byte = 0x00 (X25_IFACE_DATA)
This indicates that the rest of the skbuff contains data to be transmitted
over the LAPB link. The LAPB link should already exist before any data is
passed down.
-First Byte = 0x01
+First Byte = 0x01 (X25_IFACE_CONNECT)
Establish the LAPB link. If the link is already established then the connect
confirmation message should be returned as soon as possible.
-First Byte = 0x02
+First Byte = 0x02 (X25_IFACE_DISCONNECT)
Terminate the LAPB link. If it is already disconnected then the disconnect
confirmation message should be returned as soon as possible.
-First Byte = 0x03
+First Byte = 0x03 (X25_IFACE_PARAMS)
LAPB parameters. To be defined.
Device Driver to Packet Layer
-----------------------------
-First Byte = 0x00
+First Byte = 0x00 (X25_IFACE_DATA)
This indicates that the rest of the skbuff contains data that has been
received over the LAPB link.
-First Byte = 0x01
+First Byte = 0x01 (X25_IFACE_CONNECT)
LAPB link has been established. The same message is used for both a LAPB
link connect_confirmation and a connect_indication.
-First Byte = 0x02
+First Byte = 0x02 (X25_IFACE_DISCONNECT)
LAPB link has been terminated. This same message is used for both a LAPB
link disconnect_confirmation and a disconnect_indication.
-First Byte = 0x03
+First Byte = 0x03 (X25_IFACE_PARAMS)
LAPB parameters. To be defined.