Duplicate Address Detection Proxy
The document describes a proxy-based mechanism allowing the use of Duplicate Address Detection (DAD) by IPv6 nodes in a point-to-multipoint architecture with a "split-horizon" forwarding scheme, primarily deployed for Digital Subscriber Line (DSL) and Fiber access architectures. Based on the DAD signaling, the first-hop router stores in a Binding Table all known IPv6 addresses used on a point-to-multipoint domain (e.g., VLAN). When a node performs DAD for an address already used by another node, the first-hop router defends the address rather than the device using the address.