Juniper Networks This document specifies a mechanism for Penultimate Hop Popping (PHP) in the Bit Index Explicit Replication (BIER) architecture. PHP enables the removal of the BIER header by the penultimate router, thereby reducing the processing burden on the final router in the delivery path. This extension to BIER enhances operational efficiency by optimizing packet forwarding in scenarios where the final hop's capabilities or requirements necessitate such handling. The document details the necessary extensions to the BIER encapsulation and forwarding processes to support PHP, providing guidance for implementation and deployment within BIER-enabled networks.