The BGPSEC protocol requires a method for protection from replay attacks, at least to control the window of exposure. In the context of BGPSEC, a replay attack occurs when an adversary suppresses a prefix withdrawal (implicit or explicit) or replays a previously received BGPSEC announcement for a prefix that has since been withdrawn. This informational document provides design discussion and comparison of multiple alternative replay-attack protection mechanisms weighing their pros and cons. It is meant to be a companion document to the standards track I-D.-ietf-sidr-bgpsec- rollover that will specify a method to be used with BGPSEC for replay-attack protection.