FreeBSD gets GRAND implementation to fix IPv6 first-packet delay
A FreeBSD contributor has implemented GRAND (Gratuitous Neighbour Advertisement), a mechanism that addresses an asymmetry in IPv6 Neighbour Discovery where a host can reach its router immediately but the router may not yet know how to reach the host. Under GRAND, the host proactively announces its new IPv6 address so the router already holds a Neighbour Cache entry before any return traffic arrives.