Yes, having to put two stacks into constrained devices is certainly challenging. In the ideal world we'd either: 1. Jump ahead to a IPv6-only world and just su

Yes, having to put two stacks into constrained devices is certainly challenging. In the ideal world we'd either: 1. Jump ahead to a IPv6-only world and just support one stack; or 2. Increase the memory in devices to allow two stacks. (But of course with more memory comes more cost.)