Table of Contents Table of Contents Title and Copyright Information Preface Audience Documentation Accessibility Diversity and Inclusion 1 Network Bridge Overview About Network Bridge About the Supported Nchf Service Operations About the Supported Npcf Service Operations 2 Using Network Bridge for 5G-to-4G Payload Conversion About 5G-to-4G Payload Conversion 5G-to-4G Network Bridge Architecture Processing Messages from 5G NFs to 4G NEs Processing Messages from 4G NEs to 5G NFs 3 Using Network Bridge for 5G-to-5G Payload Conversion About Using Network Bridge as an N40 Proxy Process Flow for N40 Proxy About the Mutation Rule File