Routers that can connect to ten megabit Ethernets MAY be able to receive and forward Ethernet packets encapsulated using the trailer encapsulation described in [LINK:1]. However, a router SHOULD NOT originate trailer encapsulated packets. A router MUST NOT originate trailer encapsulated packets without first verifying, using the mechanism described in [INTRO:2], that the immediate destination of the packet is willing and able to accept trailer-encapsulated packets. A router SHOULD NOT agree (using these mechanisms) to accept trailer-encapsulated packets.