Dnssec: Retrieve Bind Server's Public Key

Hello guys,  

I've got a FreeIPA version 4.5, Centos 7.x server running their bind+ldap server. I'm a complete dnssec newbie.My eventual goal is to export the Bind server's public key so I can add it as trust anchors to Microsoft DNS server.However, I cannot make heads or tails out of how I get the public key out. I assume the key is in the LDAP server as binary data under

Please help  

I didn't find the right solution from the Internet

References:
http://bit.ly/2HmxC5f
Campus Management System Video

Thank you