hey,
IA_PD is a red herring, because it's fully independent from everything else, except that it happens to use the same mechanics as IA_NA - effectively it's different enough as far as handling in devices is concerned that it could be considered a protocol in it's own.
Unfortunately it's not different protocol and it is a great way to propagate prefix information to HGWs. And because you get other DHCP benefits like DNS and NTP propagation, LDRA inserting circuit identification information it feels natural to have default gw information as well.
-- tarko
