Juniper Networks Futurewei USA Nokia ZTE The BIER Encapsulation RFC8296 specifies that the "Proto" field in the BIER header is set to 1 if an MPLS label stack follows the BIER header and the top of the stack label is a downstream-assigned label, and is set to 2 if the top of stack label is an upstream-assigned label, which is looked up in the context-specific label forwarding table that can be derived from the BIER header. The terms upstream/downstream-assignment are inappropriate to describe the required forwarding for new MPLS label semantics such as SRGB and DCB labels as defined in RFC8402 and RFC9573 respectively. This can result in potentially inconsistent implementation choices causing potential interoperability issues. This document rectifies this situation by changing the IANA BIER Next Protocol Identifier semantic for MPLS code points from their label semantic to the required LFIB in the forwarding plane, hence covering those new type of labels without changing behavior for existing upstream/downstream-assigned labels.