2. Terminology

[RFC4271] describes a Policy Information Base (PIB) that contains local policies that can be applied to the information in the Routing Information Base (RIB). This document distinguishes the type of a policy based on its application.

Import Policy: a local policy to be applied to the information contained in the Adj-RIBs-In. As described in Section 3.2 [RFC4271], the Adj-RIBs-In contain information learned from other BGP speakers, and the application of the Import Policy results in the routes that will be considered in the Decision Process by the local BGP speaker.

Export Policy: a local policy to be applied in selecting the information contained in the Adj-RIBs-Out. As described in Section 3.2 [RFC4271], the Adj-RIBs-Out contain information that has been selected for advertisement to other BGP speakers.

2.1. Requirements Language

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.