Download of Dhcpy6d 0.4.3 for Mac was available from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. The application lies within Internet & Network Tools, more precisely Network tools. The actual developer of this free Mac application is Henri Wahl.
From the developer:
Dhcpy6d is an open source server for DHCPv6, the DHCP protocol for IPv6. Its development is driven by the need to be able to use the existing IPv4 infrastructure in coexistence with IPv6. In a dualstack scenario, the existing DHCPv4 most probably uses MAC addresses of clients to identify them.
You may want to check out more software for Mac, such as IPNetShareX, PPPoE Connector or tn3270, which might be related to Dhcpy6d.