usc.edu/CDNSKEY: The CDNSKEY RRset must be signed with a key that is represented in both the current DNSKEY and the current DS RRset. See RFC 7344, Sec. 4.1.
usc.edu/CDS: The CDS RRset must be signed with a key that is represented in both the current DNSKEY and the current DS RRset. See RFC 7344, Sec. 4.1.