2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/164318Several users of our AS relationship inference data (http://www.caida.org/data/active/as-relationships/), released with cs/0604017, asked us why it contained AS relationship cycles, e.g., cases where AS A is a provider of AS B, B is a provider of C, and C is a provider of A, or other cycle types. Having been answering these questions in private communications, we have eventually decided to write down our answers here for future reference.This note is an addendum to cs/0604017Networking and Internet ArchitectureC.2.5; C.2.1text