Outbound and Inbound RIPv2 update messages can be filtered at any interface or for the entire RIPv2 process. To filter routes the distribute-list command is used under router rip to reference an ACL or Prefix list. Any subnets matched with a permit clause in the ACL make it through, any that match the deny action are filtered. Filtering can be controlled in either direction in/out and optionally for a specific interface. If the interface is not specified all routes are filtered.