field, where the PPP Protocol field indicates either type hex 0281
(MPLS Unicast) or type hex 0283 (MPLS Multicast). The maximum length
of a labeled packet transmitted over a PPP link is the same as the
maximum length of the Information field of a PPP encapsulated packet.
The format of the Information field itself is as defined in section
2.
Note that two codepoints are defined for labeled packets; one for
multicast and one for unicast. Once the MPLSCP has reached the
Opened state, both label switched multicasts and label switched
unicasts can be sent over the PPP link.
4.4. Label Switching Control Protocol Configuration Options
There are no configuration options.
5. Transporting Labeled Packets over LAN Media
Exactly one labeled packet is carried in each frame.
The label stack entries immediately precede the network layer header,
and follow any data link layer headers, including, e.g., any 802.1Q
headers that may exist.
The ethertype value 8847 hex is used to indicate that a frame is
carrying an MPLS unicast packet.