Tunneling of classified traffic across an unclassified IP transport network must employ cryptographic algorithms in accordance with CNSS Policy No. 15.

When transporting classified data over an unclassified IP network, it is imperative that traffic from the classified enclave or community of interest is encrypted prior reaching the point of presence or service delivery node of the unclassified network. Confidentiality and integrity of the classified traffic must be preserved by employing cryptographic algorithms in accordance with CNSS Policy No. 15 which requires the appropriate Suite B cryptographic algorithms listed in ANNEX B or a commensurate suite of NSA-approved cryptographic algorithms.