Cisco Systems Cisco Systems ISC The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) specification defined two stateful options, IA_NA and IA_TA, but did not anticipate the development of additional stateful options. DHCPv6 Prefix Delegation added the IA_PD option, which is stateful. Applications that use IA_NA and IA_PD together have revealed issues that need to be addressed. This document updates RFCs 3315 and 3633 to address these issues.