In general, some embodiments described herein relate to using agile or dynamic addresses for multicasting that may be difficult or impossible for a malicious actor to predict. Such agile addresses may prevent a malicious actor from attacking a single static multicast address and may prevent the architecture of the multicast network from propagating the attack. Data sent to invalid (e.g., expired, revoked, and/or otherwise depreciated addresses) can be filtered out and dropped from the network. For example, a first group key associated with a first time period can be calculated based on a first shared secret and a second group key associated with a second time period can be calculated based on a second shared secret. At any given time at least one group key can be an accepted group key. When a multicast address includes a currently accepted group key, the data can be sent to a group.