MPLS label stack
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This document defines how to encapsulate an MPLS label stack and its
payload inside the L2TPv3 ...
... L2TPv3 encapsulation
defined in [RFC3931]. The MPLS Label Stack and payload are carried
in their entirety following IP ...
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The L2TPv3 encapsulation carrying a single MPLS label stack entry is
as follows:
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... Label Stack Entry
An MPLS label stack entry as defined in [RFC3032].
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... authentication and integrity provided will
apply to the entire MPLS packet, including the MPLS label stack.)
Consequently, the implementation MUST support Encapsulating Security
Payload ...
... Rosen, E., Tappan, D., Fedorkow, G., Rekhter, Y., Farinacci, D., Li, T., and A. Conta, "MPLS Label Stack Encoding", RFC 3032prop, January 2001. ...