6.1. Protocol Security Considerations

The procedures and protocol extensions in this document do not affect the OSPFv2 security model. See [RFC7684] for OSPFv2 security discussion.

The AC-Flag MUST be either set or clear, and it introduces operational dependencies that affect semantic validity of the advertised prefix. Receivers MUST consider possible misconfiguration or inconsistent implementation when using AC-Flag for forwarding or security decisions.