Type Number,Cert Format,Reference
0,Reserved,[RFC8002]
1,X.509 v3,[RFC8002]
2,Obsoleted,[RFC8002]
3,Hash and URL of X.509 v3,[RFC8002]
4,Obsoleted,[RFC8002]
5,LDAP URL of X.509 v3,[RFC8002]
6,Obsoleted,[RFC8002]
7,Distinguished Name of X.509 v3,[RFC8002]
8,Obsoleted,[RFC8002]
9-255,Unassigned,