IANA Registrations for the BGP Finite State Machine (FSM)

Abstract

The Border Gateway Protocol, version 4 (BGP-4) finite state machine (FSM) is defined in RFC 4271. Over the years, various extensions to BGP have been authored that update the protocol's FSM. Some elements of the FSM are enumerated. Those elements are referred to across BGP extensions in their respective state machine changes, and may also be used for management purposes in things such as YANG (RFC 7950).¶

To provide consistent naming and enumeration of these FSM elements, this document requests IANA to create and maintain registries for elements in the BGP FSM.¶

1. Introduction

Section 8 of [RFC4271] defines BGP's finite state machine (FSM). Some elements of the FSM are enumerated. These include:¶

• Session attributes (variables), which may be:¶

  • Mandatory and MUST be supported by all BGP-4 implementations on all BGP connections.¶
  • Optional and MAY be supported, either per connection or per local system.¶

• Events, which may be:¶

  • Administrative events.¶
  • Timer events.¶
  • TCP connection-based events.¶
  • BGP message-based events.¶

While the core FSM is defined in [RFC4271], extensions specified in other BGP documents may update FSM procedures. Consistent enumeration and naming of these FSM elements is necessary for procedural clarity. Additionally, management mechanisms such as YANG [RFC7950] modules may expose BGP protocol state covered by these elements.¶

This document requests IANA to create and maintain appropriate registries for these FSM elements.¶

4. References