The router sets the Ethertype field value of the outgoing packet to the MPLS value.
The router checks and decrements the TTL field of the received IPv4 or IPv6 header and sets the TTL of all labels of the label stack specified in the pushed-labels command according to the following rules:
The router propagates the decremented TTL of the received IPv4 or IPv6 packet into all labels of the pushed label stack for a prefix in GRT.
The router then follows the configuration of the TTL propagation in the case of a IPv4 or IPv6 prefix forwarded in a VPRN context:
— config>router>ttl-propagate>vprn-local {none | vc-only | all}
— config>router>ttl-propagate>vprn-transit {none | vc-only | all}
— config>service>vprn>ttl-propagate>local {inherit | none | vc-only | all}
— config>service>vprn>ttl-propagate>transit {inherit | none | vc-only | all}
When a IPv6 packet in GRT is forwarded using an endpoint policy with an IPv4 endpoint, the IPv6 explicit null label is pushed first before the label stack specified in the pushed-labels command.