You can form a unified database of route policies that the protocols (RIP, OSPF or Border Gateway Protocol [BGP]) can use for any type of filtering task.
For information about configuring a prefix list, see Configuring a prefix list. For more information about community list, see Configure a Community Access List. For more information about AS path list, see Configure an AS Path List.
A name or an ID identifies a policy. Under a policy you can have several sequence numbers, each of which is equal to one policy in the old convention. If a field in a policy is not configured, the system displays it as 0 or any when the system displays it in Enterprise Device Manager (EDM). This means that the field is ignored in the match criteria. You can use the clear option to remove existing configurations for any field.
Each policy sequence number contains a set of fields. Only a subset of those fields is used when the policy is applied in a certain context. For example, if a policy has a set-preference field set, it is used only when the policy is applied for accept purposes. This field is ignored when the policy is applied for announce and redistribute purposes.
You can apply only one policy for one purpose (for example, RIP Announce on a given RIP interface). In that example, all sequence numbers under the given policy are applicable for that filter. A sequence number also acts as an implicit preference: a lower sequence number is preferred.