Stateful Double Translation and Encapsulation

This chapter explores stateful double transition and encapsulation technologies for IPv4/IPv6 coexistence, focusing on three key mechanisms: Stateful Double Translation (464XLAT), Stateful Tunneling (DS-Lite), and Subscriber State Tunneling (LW-4o6). These solutions address challenges in network migration by enabling IPv4 communication cross IPv6-only networks. Stateful approaches centralize state management in core network infrastructure, simplifying user-side equipment by keeping them stateless. While this reduces deployment complexity for end-users, it introduces scalability and security limitations due to core network state dependencies. The chapter emphasizes evaluating trade-offs between ease of deployment and network efficiency, recommending prioritizing stateless alternatives when feasible.